diff --git a/CHANGELOG.md b/CHANGELOG.md
index 36b5ba67..9865212c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,15 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## Unreleased
 
+## [4.8.1] - 2020-07-03
+
+### Changed
+- updated grel-functions-java to 0.5.2
+
+### Fixed
+- ObjectMap with type Blank Node is ignored (see [issue 164](https://gitlab.ilabt.imec.be/rml/proc/rmlmapper-java/-/issues/164))
+- Support double quotes in references of RDBs (see [issue 163](https://gitlab.ilabt.imec.be/rml/proc/rmlmapper-java/-/issues/163))
+
 ## [4.8.0] - 2020-05-25
 
 ### Added
@@ -261,6 +270,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - support for accessing remote files (via HTTP GET)
 - basic support for functions
 
+[4.8.1]: https://github.com/RMLio/rmlmapper-java/compare/v4.8.0...v4.8.1
 [4.8.0]: https://github.com/RMLio/rmlmapper-java/compare/v4.7.0...v4.8.0
 [4.7.0]: https://github.com/RMLio/rmlmapper-java/compare/v4.6.0...v4.7.0
 [4.6.0]: https://github.com/RMLio/rmlmapper-java/compare/v4.5.1...v4.6.0
diff --git a/buildNumber.properties b/buildNumber.properties
index 737a21ca..028a69a1 100644
--- a/buildNumber.properties
+++ b/buildNumber.properties
@@ -1,3 +1,3 @@
 #maven.buildNumber.plugin properties file
-#Mon May 25 08:33:31 CEST 2020
-buildNumber0=246
+#Fri Jul 03 09:44:11 CEST 2020
+buildNumber0=259
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index 63a3722d..40186086 100644
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-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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index ad25961e..e55dc795 100644
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index 835a05f0..15434a89 100644
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+<meta name="dc.created" content="2020-06-11">
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index fbe18f93..a49cfa75 100644
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index 84e63f4d..2bab33d3 100644
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+<meta name="dc.created" content="2020-06-11">
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+<meta name="dc.created" content="2020-06-11">
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index eea218ae..b0a56ac6 100644
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--- a/docs/apidocs/be/ugent/rml/termgenerator/class-use/LiteralGenerator.html
+++ b/docs/apidocs/be/ugent/rml/termgenerator/class-use/LiteralGenerator.html
@@ -2,10 +2,10 @@
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-<title>Uses of Class be.ugent.rml.termgenerator.LiteralGenerator (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Uses of Class be.ugent.rml.termgenerator.LiteralGenerator (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Uses of Class be.ugent.rml.termgenerator.LiteralGenerator (rmlmapper 4.7.0 API)";
+            parent.document.title="Uses of Class be.ugent.rml.termgenerator.LiteralGenerator (rmlmapper 4.8.0 API)";
         }
     }
     catch(err) {
diff --git a/docs/apidocs/be/ugent/rml/termgenerator/class-use/NamedNodeGenerator.html b/docs/apidocs/be/ugent/rml/termgenerator/class-use/NamedNodeGenerator.html
index 02cd7c50..6de7f818 100644
--- a/docs/apidocs/be/ugent/rml/termgenerator/class-use/NamedNodeGenerator.html
+++ b/docs/apidocs/be/ugent/rml/termgenerator/class-use/NamedNodeGenerator.html
@@ -2,10 +2,10 @@
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-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Uses of Class be.ugent.rml.termgenerator.NamedNodeGenerator (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Uses of Class be.ugent.rml.termgenerator.NamedNodeGenerator (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
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         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Uses of Class be.ugent.rml.termgenerator.NamedNodeGenerator (rmlmapper 4.7.0 API)";
+            parent.document.title="Uses of Class be.ugent.rml.termgenerator.NamedNodeGenerator (rmlmapper 4.8.0 API)";
         }
     }
     catch(err) {
diff --git a/docs/apidocs/be/ugent/rml/termgenerator/class-use/TermGenerator.html b/docs/apidocs/be/ugent/rml/termgenerator/class-use/TermGenerator.html
index 256c9b53..940c735d 100644
--- a/docs/apidocs/be/ugent/rml/termgenerator/class-use/TermGenerator.html
+++ b/docs/apidocs/be/ugent/rml/termgenerator/class-use/TermGenerator.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Uses of Class be.ugent.rml.termgenerator.TermGenerator (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Uses of Class be.ugent.rml.termgenerator.TermGenerator (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
 <link rel="stylesheet" type="text/css" href="../../../../../stylesheet.css" title="Style">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
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         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Uses of Class be.ugent.rml.termgenerator.TermGenerator (rmlmapper 4.7.0 API)";
+            parent.document.title="Uses of Class be.ugent.rml.termgenerator.TermGenerator (rmlmapper 4.8.0 API)";
         }
     }
     catch(err) {
diff --git a/docs/apidocs/be/ugent/rml/termgenerator/package-summary.html b/docs/apidocs/be/ugent/rml/termgenerator/package-summary.html
index c7bf7feb..a96e0397 100644
--- a/docs/apidocs/be/ugent/rml/termgenerator/package-summary.html
+++ b/docs/apidocs/be/ugent/rml/termgenerator/package-summary.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>be.ugent.rml.termgenerator (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>be.ugent.rml.termgenerator (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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 <link rel="stylesheet" type="text/css" href="../../../../jquery/jquery-ui.css" title="Style">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="be.ugent.rml.termgenerator (rmlmapper 4.7.0 API)";
+            parent.document.title="be.ugent.rml.termgenerator (rmlmapper 4.8.0 API)";
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     }
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diff --git a/docs/apidocs/be/ugent/rml/termgenerator/package-tree.html b/docs/apidocs/be/ugent/rml/termgenerator/package-tree.html
index 49c24d8a..c9690017 100644
--- a/docs/apidocs/be/ugent/rml/termgenerator/package-tree.html
+++ b/docs/apidocs/be/ugent/rml/termgenerator/package-tree.html
@@ -2,10 +2,10 @@
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-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>be.ugent.rml.termgenerator Class Hierarchy (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>be.ugent.rml.termgenerator Class Hierarchy (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="be.ugent.rml.termgenerator Class Hierarchy (rmlmapper 4.7.0 API)";
+            parent.document.title="be.ugent.rml.termgenerator Class Hierarchy (rmlmapper 4.8.0 API)";
         }
     }
     catch(err) {
diff --git a/docs/apidocs/be/ugent/rml/termgenerator/package-use.html b/docs/apidocs/be/ugent/rml/termgenerator/package-use.html
index 7c908a08..59f32433 100644
--- a/docs/apidocs/be/ugent/rml/termgenerator/package-use.html
+++ b/docs/apidocs/be/ugent/rml/termgenerator/package-use.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
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-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Uses of Package be.ugent.rml.termgenerator (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Uses of Package be.ugent.rml.termgenerator (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
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         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Uses of Package be.ugent.rml.termgenerator (rmlmapper 4.7.0 API)";
+            parent.document.title="Uses of Package be.ugent.rml.termgenerator (rmlmapper 4.8.0 API)";
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diff --git a/docs/apidocs/constant-values.html b/docs/apidocs/constant-values.html
index 69356d60..6c5f1d19 100644
--- a/docs/apidocs/constant-values.html
+++ b/docs/apidocs/constant-values.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Constant Field Values (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Constant Field Values (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
 <link rel="stylesheet" type="text/css" href="stylesheet.css" title="Style">
 <link rel="stylesheet" type="text/css" href="jquery/jquery-ui.css" title="Style">
 <script type="text/javascript" src="script.js"></script>
@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Constant Field Values (rmlmapper 4.7.0 API)";
+            parent.document.title="Constant Field Values (rmlmapper 4.8.0 API)";
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diff --git a/docs/apidocs/deprecated-list.html b/docs/apidocs/deprecated-list.html
index 8b7ca19c..c91fb969 100644
--- a/docs/apidocs/deprecated-list.html
+++ b/docs/apidocs/deprecated-list.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Deprecated List (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Deprecated List (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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 <link rel="stylesheet" type="text/css" href="jquery/jquery-ui.css" title="Style">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Deprecated List (rmlmapper 4.7.0 API)";
+            parent.document.title="Deprecated List (rmlmapper 4.8.0 API)";
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     }
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diff --git a/docs/apidocs/help-doc.html b/docs/apidocs/help-doc.html
index 884d9d4e..fc53fce7 100644
--- a/docs/apidocs/help-doc.html
+++ b/docs/apidocs/help-doc.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>API Help (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>API Help (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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 <script type="text/javascript"><!--
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-            parent.document.title="API Help (rmlmapper 4.7.0 API)";
+            parent.document.title="API Help (rmlmapper 4.8.0 API)";
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diff --git a/docs/apidocs/index-all.html b/docs/apidocs/index-all.html
index 9cbe6ade..c730c9c0 100644
--- a/docs/apidocs/index-all.html
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@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
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-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Index (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Index (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Index (rmlmapper 4.7.0 API)";
+            parent.document.title="Index (rmlmapper 4.8.0 API)";
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diff --git a/docs/apidocs/index.html b/docs/apidocs/index.html
index 159fa5d2..b158d768 100644
--- a/docs/apidocs/index.html
+++ b/docs/apidocs/index.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Overview (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Overview (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
 <link rel="stylesheet" type="text/css" href="stylesheet.css" title="Style">
 <link rel="stylesheet" type="text/css" href="jquery/jquery-ui.css" title="Style">
 <script type="text/javascript" src="script.js"></script>
@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Overview (rmlmapper 4.7.0 API)";
+            parent.document.title="Overview (rmlmapper 4.8.0 API)";
         }
     }
     catch(err) {
@@ -78,7 +78,7 @@
 </header>
 <main role="main">
 <div class="header">
-<h1 class="title">rmlmapper 4.7.0 API</h1>
+<h1 class="title">rmlmapper 4.8.0 API</h1>
 </div>
 <div class="contentContainer">
 <div class="overviewSummary">
diff --git a/docs/apidocs/member-search-index.zip b/docs/apidocs/member-search-index.zip
index a7498124..3ab57469 100644
Binary files a/docs/apidocs/member-search-index.zip and b/docs/apidocs/member-search-index.zip differ
diff --git a/docs/apidocs/options b/docs/apidocs/options
index 62d1d693..f14b150a 100644
--- a/docs/apidocs/options
+++ b/docs/apidocs/options
@@ -18,10 +18,10 @@
 'UTF-8'
 -Xdoclint:none
 -doctitle
-'rmlmapper 4.7.0 API'
+'rmlmapper 4.8.0 API'
 -linkoffline
 'https://docs.oracle.com/javase/8/docs/api' '/home/pieter/Developer/rmlmapper-java/target/javadoc-bundle-options'
 -use
 -version
 -windowtitle
-'rmlmapper 4.7.0 API'
\ No newline at end of file
+'rmlmapper 4.8.0 API'
\ No newline at end of file
diff --git a/docs/apidocs/overview-summary.html b/docs/apidocs/overview-summary.html
index e2afee91..4c051298 100644
--- a/docs/apidocs/overview-summary.html
+++ b/docs/apidocs/overview-summary.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>rmlmapper 4.7.0 API</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>rmlmapper 4.8.0 API</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
 <script type="text/javascript">window.location.replace('index.html')</script>
 <noscript>
 <meta http-equiv="Refresh" content="0;index.html">
diff --git a/docs/apidocs/overview-tree.html b/docs/apidocs/overview-tree.html
index 01be4426..761c274f 100644
--- a/docs/apidocs/overview-tree.html
+++ b/docs/apidocs/overview-tree.html
@@ -2,10 +2,10 @@
 <!-- NewPage -->
 <html lang="en">
 <head>
-<!-- Generated by javadoc (12.0.2) on Tue May 12 13:12:10 CEST 2020 -->
-<title>Class Hierarchy (rmlmapper 4.7.0 API)</title>
+<!-- Generated by javadoc (12.0.2) on Thu Jun 11 08:30:32 CEST 2020 -->
+<title>Class Hierarchy (rmlmapper 4.8.0 API)</title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<meta name="dc.created" content="2020-05-12">
+<meta name="dc.created" content="2020-06-11">
 <link rel="stylesheet" type="text/css" href="stylesheet.css" title="Style">
 <link rel="stylesheet" type="text/css" href="jquery/jquery-ui.css" title="Style">
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@@ -22,7 +22,7 @@
 <script type="text/javascript"><!--
     try {
         if (location.href.indexOf('is-external=true') == -1) {
-            parent.document.title="Class Hierarchy (rmlmapper 4.7.0 API)";
+            parent.document.title="Class Hierarchy (rmlmapper 4.8.0 API)";
         }
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diff --git a/docs/apidocs/package-search-index.zip b/docs/apidocs/package-search-index.zip
index 496eccdb..38078461 100644
Binary files a/docs/apidocs/package-search-index.zip and b/docs/apidocs/package-search-index.zip differ
diff --git a/docs/apidocs/type-search-index.zip b/docs/apidocs/type-search-index.zip
index 4a5d35e9..03edaebc 100644
Binary files a/docs/apidocs/type-search-index.zip and b/docs/apidocs/type-search-index.zip differ
diff --git a/pom.xml b/pom.xml
index 81af65bf..53f42ce5 100644
--- a/pom.xml
+++ b/pom.xml
@@ -2,7 +2,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>be.ugent.rml</groupId>
     <artifactId>rmlmapper</artifactId>
-    <version>4.8.0</version>
+    <version>4.8.1</version>
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <junit.version>4.12</junit.version>
@@ -137,7 +137,7 @@
         <dependency>
             <groupId>com.github.fnoio</groupId>
             <artifactId>grel-functions-java</artifactId>
-            <version>v0.4.0</version>
+            <version>v0.5.2</version>
         </dependency>
     </dependencies>
 
diff --git a/src/main/java/be/ugent/rml/MappingFactory.java b/src/main/java/be/ugent/rml/MappingFactory.java
index e48215c6..e47b2baa 100644
--- a/src/main/java/be/ugent/rml/MappingFactory.java
+++ b/src/main/java/be/ugent/rml/MappingFactory.java
@@ -14,7 +14,6 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.naming.Name;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -31,6 +30,9 @@ public class MappingFactory {
     private Term triplesMap;
     private QuadStore store;
     private List<PredicateObjectGraphMapping> predicateObjectGraphMappings;
+    // This boolean is true when the double in a reference need to be ignored.
+    // For example, when accessing data in a RDB.
+    private boolean ignoreDoubleQuotes;
     protected Logger logger = LoggerFactory.getLogger(this.getClass());
 
     public MappingFactory(FunctionLoader functionLoader) {
@@ -43,6 +45,7 @@ public Mapping createMapping(Term triplesMap, QuadStore store) throws Exception
         this.subjectMappingInfo = null;
         this.predicateObjectGraphMappings = new ArrayList<>();
         this.graphMappingInfos = null;
+        this.ignoreDoubleQuotes = this.areDoubleQuotesIgnored(store, triplesMap);
 
         parseSubjectMap();
         parsePredicateObjectMaps();
@@ -71,7 +74,7 @@ private void parseSubjectMap() throws Exception {
 
                     //checking if we are dealing with a Blank Node as subject
                     if (!termTypes.isEmpty() && termTypes.get(0).equals(new NamedNode(NAMESPACES.RR  + "BlankNode"))) {
-                        SingleRecordFunctionExecutor executor = RecordFunctionExecutorFactory.generate(store, subjectmap, true);
+                        SingleRecordFunctionExecutor executor = RecordFunctionExecutorFactory.generate(store, subjectmap, true, ignoreDoubleQuotes);
 
                         if (executor != null) {
                             generator = new BlankNodeGenerator(executor);
@@ -80,7 +83,7 @@ private void parseSubjectMap() throws Exception {
                         }
                     } else {
                         //we are not dealing with a Blank Node, so we create the template
-                        generator = new NamedNodeGenerator(RecordFunctionExecutorFactory.generate(store, subjectmap, true));
+                        generator = new NamedNodeGenerator(RecordFunctionExecutorFactory.generate(store, subjectmap, true, ignoreDoubleQuotes));
                     }
                 } else {
                     SingleRecordFunctionExecutor functionExecutor = parseFunctionTermMap(functionValues.get(0));
@@ -186,9 +189,9 @@ private void parseObjectMapWithCallback(Term objectmap, BiConsumer<MappingInfo,
 
         if (functionValues.isEmpty()) {
             boolean encodeIRI = termType != null && termType.getValue().equals(NAMESPACES.RR + "IRI");
-            SingleRecordFunctionExecutor executor = RecordFunctionExecutorFactory.generate(store, objectmap, encodeIRI);
+            SingleRecordFunctionExecutor executor = RecordFunctionExecutorFactory.generate(store, objectmap, encodeIRI, ignoreDoubleQuotes);
 
-            if (executor != null) {
+            if (parentTriplesMaps.isEmpty() && parentTermMaps.isEmpty()) {
                 TermGenerator oGen;
 
                 if (termType.equals(new NamedNode(NAMESPACES.RR + "Literal"))) {
@@ -204,7 +207,12 @@ private void parseObjectMapWithCallback(Term objectmap, BiConsumer<MappingInfo,
                 } else if (termType.equals(new NamedNode(NAMESPACES.RR + "IRI"))) {
                     oGen = new NamedNodeGenerator(executor);
                 } else {
-                    oGen = new BlankNodeGenerator(executor);
+                    if (executor == null) {
+                        // This will generate Blank Node with random identifiers.
+                        oGen = new BlankNodeGenerator();
+                    } else {
+                        oGen = new BlankNodeGenerator(executor);
+                    }
                 }
 
                 objectMapCallback.accept(new MappingInfo(objectmap, oGen), "child");
@@ -232,11 +240,12 @@ private void parseObjectMapWithCallback(Term objectmap, BiConsumer<MappingInfo,
                         FunctionModel equal = functionLoader.getFunction(new NamedNode("http://example.com/idlab/function/equal"));
                         Map<String, Object[]> parameters = new HashMap<>();
 
-                        SingleRecordFunctionExecutor parent = new ReferenceExtractor(parents.get(0));
+                        boolean ignoreDoubleQuotesInParent = this.areDoubleQuotesIgnored(store, parentTriplesMap);
+                        SingleRecordFunctionExecutor parent = new ReferenceExtractor(parents.get(0), ignoreDoubleQuotesInParent);
                         Object[] detailsParent = {"parent", parent};
                         parameters.put("http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter", detailsParent);
 
-                        SingleRecordFunctionExecutor child = new ReferenceExtractor(childs.get(0));
+                        SingleRecordFunctionExecutor child = new ReferenceExtractor(childs.get(0), ignoreDoubleQuotes);
                         Object[] detailsChild = {"child", child};
                         parameters.put("http://users.ugent.be/~bjdmeest/function/grel.ttl#valueParameter2", detailsChild);
 
@@ -301,7 +310,7 @@ private List<MappingInfo> parseGraphMapsAndShortcuts(Term termMap) throws Except
             TermGenerator generator;
 
             if (functionValues.isEmpty()) {
-                SingleRecordFunctionExecutor executor = RecordFunctionExecutorFactory.generate(store, graphMap, true);
+                SingleRecordFunctionExecutor executor = RecordFunctionExecutorFactory.generate(store, graphMap, true, ignoreDoubleQuotes);
 
                 if (termType == null || termType.equals(new NamedNode(NAMESPACES.RR + "IRI"))) {
                     generator = new NamedNodeGenerator(executor);
@@ -346,7 +355,7 @@ private List<MappingInfo> parsePredicateMapsAndShortcuts(Term termMap) throws IO
 
             if (functionValues.isEmpty()) {
                 predicateMappingInfos.add(new MappingInfo(predicateMap,
-                        new NamedNodeGenerator(RecordFunctionExecutorFactory.generate(store, predicateMap, false))));
+                        new NamedNodeGenerator(RecordFunctionExecutorFactory.generate(store, predicateMap, false, ignoreDoubleQuotes))));
             } else {
                 SingleRecordFunctionExecutor functionExecutor = parseFunctionTermMap(functionValues.get(0));
 
@@ -449,7 +458,7 @@ private List<SingleRecordFunctionExecutor> getLanguageExecutorsForObjectMap(Term
             List<Term> functionValues = Utils.getObjectsFromQuads(store.getQuads(languageMap, new NamedNode(NAMESPACES.FNML + "functionValue"), null));
 
             if (functionValues.isEmpty()) {
-                executors.add(RecordFunctionExecutorFactory.generate(store, languageMap, false));
+                executors.add(RecordFunctionExecutorFactory.generate(store, languageMap, false, ignoreDoubleQuotes));
             } else {
                 executors.add(parseFunctionTermMap(functionValues.get(0)));
             }
@@ -516,4 +525,31 @@ private List<PredicateObjectGraphMapping> getPredicateObjectGraphMappingFromMult
         return list;
     }
 
+    /**
+     * This function returns true if double quotes should be ignored in references.
+     * @param store The store with the RML rules.
+     * @param triplesMap The Triples Map that should be checked.
+     * @return true if double quotes should be ignored in references, else false.
+     */
+    private boolean areDoubleQuotesIgnored(QuadStore store, Term triplesMap) {
+        List<Term> logicalSources = Utils.getObjectsFromQuads(store.getQuads(triplesMap, new NamedNode(NAMESPACES.RML + "logicalSource"), null));
+
+        if (!logicalSources.isEmpty()) {
+            Term logicalSource = logicalSources.get(0);
+
+            List<Term> sources = Utils.getObjectsFromQuads(store.getQuads(logicalSource, new NamedNode(NAMESPACES.RML + "source"), null));
+
+            if (!sources.isEmpty()) {
+                Term source = sources.get(0);
+
+                if (! (sources.get(0) instanceof Literal)) {
+                    List<Term> sourceType = Utils.getObjectsFromQuads(store.getQuads(source, new NamedNode(NAMESPACES.RDF + "type"), null));
+
+                    return sourceType.get(0).getValue().equals(NAMESPACES.D2RQ + "Database");
+                }
+            }
+        }
+
+        return false;
+    }
 }
diff --git a/src/main/java/be/ugent/rml/MyFileUtils.java b/src/main/java/be/ugent/rml/MyFileUtils.java
index 2d2fef30..2ac42926 100644
--- a/src/main/java/be/ugent/rml/MyFileUtils.java
+++ b/src/main/java/be/ugent/rml/MyFileUtils.java
@@ -119,4 +119,23 @@ public File getFile() throws IOException {
         }
 
     }
+
+    /**
+     * This method returns the path of the parent of a file.
+     * @param c The class to which the file path is relative.
+     * @param path The path of the file.
+     * @return The path of the parent.
+     */
+    public static String getParentPath(Class c, String path) {
+        ClassLoader classLoader = c.getClassLoader();
+        URL url = classLoader.getResource(path);
+
+        if (url != null) {
+            path = url.getFile();
+        }
+
+        File outputFile = new File(path);
+
+        return outputFile.getParent();
+    }
 }
diff --git a/src/main/java/be/ugent/rml/RecordFunctionExecutorFactory.java b/src/main/java/be/ugent/rml/RecordFunctionExecutorFactory.java
index 7c04c327..d2bf7865 100644
--- a/src/main/java/be/ugent/rml/RecordFunctionExecutorFactory.java
+++ b/src/main/java/be/ugent/rml/RecordFunctionExecutorFactory.java
@@ -12,15 +12,15 @@
 
 public class RecordFunctionExecutorFactory {
 
-    public static SingleRecordFunctionExecutor generate(QuadStore store, Term termMap, boolean encodeURI) {
+    public static SingleRecordFunctionExecutor generate(QuadStore store, Term termMap, boolean encodeURI, boolean ignoreDoubleQuotes) {
         List<Term> references = Utils.getObjectsFromQuads(store.getQuads(termMap, new NamedNode(NAMESPACES.RML + "reference"), null));
         List<Term> templates = Utils.getObjectsFromQuads(store.getQuads(termMap, new NamedNode(NAMESPACES.RR + "template"), null));
         List<Term> constants = Utils.getObjectsFromQuads(store.getQuads(termMap, new NamedNode(NAMESPACES.RR + "constant"), null));
 
         if (!references.isEmpty()) {
-            return new ReferenceExtractor(references.get(0).getValue());
+            return new ReferenceExtractor(references.get(0).getValue(), ignoreDoubleQuotes);
         } else if (!templates.isEmpty()) {
-            return new ConcatFunction(Utils.parseTemplate(templates.get(0).getValue()), encodeURI);
+            return new ConcatFunction(Utils.parseTemplate(templates.get(0).getValue(), ignoreDoubleQuotes), encodeURI);
         } else if (!constants.isEmpty()) {
             return new ConstantExtractor(constants.get(0).getValue());
         } else {
diff --git a/src/main/java/be/ugent/rml/Utils.java b/src/main/java/be/ugent/rml/Utils.java
index 8ca36be3..3f8f5ebf 100644
--- a/src/main/java/be/ugent/rml/Utils.java
+++ b/src/main/java/be/ugent/rml/Utils.java
@@ -360,7 +360,7 @@ public static int getFreePortNumber() throws IOException {
      * @param template template string
      * @return list of extractors
      **/
-    public static List<Extractor> parseTemplate(String template) {
+    public static List<Extractor> parseTemplate(String template, boolean ignoreDoubleQuotes) {
         ArrayList<Extractor> extractors = new ArrayList<>();
         String current = "";
         boolean previousWasBackslash = false;
@@ -389,7 +389,7 @@ public static List<Extractor> parseTemplate(String template) {
                         current += c;
                         previousWasBackslash = false;
                     } else if (variableBusy) {
-                        extractors.add(new ReferenceExtractor(current));
+                        extractors.add(new ReferenceExtractor(current, ignoreDoubleQuotes));
                         current = "";
                         variableBusy = false;
                     } else {
diff --git a/src/main/java/be/ugent/rml/extractor/ReferenceExtractor.java b/src/main/java/be/ugent/rml/extractor/ReferenceExtractor.java
index c7d9631d..149e6f57 100644
--- a/src/main/java/be/ugent/rml/extractor/ReferenceExtractor.java
+++ b/src/main/java/be/ugent/rml/extractor/ReferenceExtractor.java
@@ -9,14 +9,26 @@
 public class ReferenceExtractor implements Extractor, SingleRecordFunctionExecutor {
 
     public String reference;
+    private boolean ignoreDoubleQuotes;
 
-    public ReferenceExtractor(String reference) {
+    public ReferenceExtractor(String reference, boolean ignoreDoubleQuotes) {
         this.reference = reference;
+        this.ignoreDoubleQuotes = ignoreDoubleQuotes;
+    }
+
+    public ReferenceExtractor(String reference) {
+        this(reference, false);
     }
 
     @Override
     public List<Object> extract(Record record) {
-        return record.get(reference);
+        String temp = this.reference;
+
+        if (ignoreDoubleQuotes && temp.startsWith("\"") && temp.endsWith("\"")) {
+            temp = temp.substring(1, temp.length() - 1);
+        }
+
+        return record.get(temp);
     }
 
     @Override
diff --git a/src/test/java/be/ugent/rml/Mapper_CSV_Test.java b/src/test/java/be/ugent/rml/Mapper_CSV_Test.java
index 34d10668..9bf600c7 100644
--- a/src/test/java/be/ugent/rml/Mapper_CSV_Test.java
+++ b/src/test/java/be/ugent/rml/Mapper_CSV_Test.java
@@ -253,4 +253,14 @@ public void evaluate_1015_CSV() {
     public void evaluate_1017_CSV() {
         doMapping("test-cases/RMLTC1017-CSV/mapping.ttl", "test-cases/RMLTC1017-CSV/output.nq");
     }
+
+    @Test
+    public void evaluate_1018_CSV() {
+        doMapping("test-cases/RMLTC1018-CSV/mapping.ttl", "test-cases/RMLTC1018-CSV/output.nq");
+    }
+
+    @Test
+    public void evaluate_1019_CSV() {
+        doMapping("test-cases/RMLTC1019-CSV/mapping.ttl", "test-cases/RMLTC1019-CSV/output.nq");
+    }
 }
\ No newline at end of file
diff --git a/src/test/java/be/ugent/rml/Mapper_MySQL_Test.java b/src/test/java/be/ugent/rml/Mapper_MySQL_Test.java
index acfeea7b..b64790d7 100644
--- a/src/test/java/be/ugent/rml/Mapper_MySQL_Test.java
+++ b/src/test/java/be/ugent/rml/Mapper_MySQL_Test.java
@@ -12,6 +12,8 @@
 
 import java.util.Arrays;
 
+import static be.ugent.rml.MyFileUtils.getParentPath;
+
 @RunWith(Parameterized.class)
 public class Mapper_MySQL_Test extends MySQLTestCore {
 
@@ -105,6 +107,8 @@ public static Iterable<Object[]> data() {
                 {"RMLTC0019b", null},
                 {"RMLTC0020a", null},
                 {"RMLTC0020b", null},
+                {"RMLTC1019", null},
+                {"RMLTC1020", null}
         });
     }
 
@@ -124,9 +128,10 @@ private void mappingTest(String testCaseName, Class expectedException) throws Ex
         mysqlDB.source(resourcePath);
 
         // mapping
+        String parentPath = getParentPath(getClass(), outputPath);
 
         if (expectedException == null) {
-            doMapping(tempMappingPath, outputPath);
+            doMapping(tempMappingPath, outputPath, parentPath);
         } else {
             doMappingExpectError(tempMappingPath);
         }
diff --git a/src/test/java/be/ugent/rml/TestCore.java b/src/test/java/be/ugent/rml/TestCore.java
index 29ab2772..ad267acd 100644
--- a/src/test/java/be/ugent/rml/TestCore.java
+++ b/src/test/java/be/ugent/rml/TestCore.java
@@ -25,7 +25,11 @@ public abstract class TestCore {
     final Logger logger = LoggerFactory.getLogger(this.getClass());
 
     Executor createExecutor(String mapPath) throws Exception {
-        return createExecutor(mapPath, new ArrayList<>());
+        return createExecutor(mapPath, new ArrayList<>(), null);
+    }
+
+    Executor createExecutor(String mapPath, List<Quad> extraQuads) throws Exception {
+        return createExecutor(mapPath, extraQuads, null);
     }
 
     /**
@@ -36,7 +40,7 @@ Executor createExecutor(String mapPath) throws Exception {
      * @return An executor.
      * @throws Exception
      */
-    Executor createExecutor(String mapPath, List<Quad> extraQuads) throws Exception {
+    Executor createExecutor(String mapPath, List<Quad> extraQuads, String parentPath) throws Exception {
         ClassLoader classLoader = getClass().getClassLoader();
         // execute mapping file
         URL url = classLoader.getResource(mapPath);
@@ -47,10 +51,19 @@ Executor createExecutor(String mapPath, List<Quad> extraQuads) throws Exception
 
         File mappingFile = new File(mapPath);
         QuadStore rmlStore = QuadStoreFactory.read(mappingFile);
+
+        if (parentPath == null) {
+            parentPath = mappingFile.getParent();
+        }
+
         rmlStore.addQuads(extraQuads);
 
         return new Executor(rmlStore,
-                new RecordsFactory(mappingFile.getParent()), Utils.getBaseDirectiveTurtle(mappingFile));
+                new RecordsFactory(parentPath), Utils.getBaseDirectiveTurtle(mappingFile));
+    }
+
+    Executor createExecutor(String mapPath, String parentPath) throws Exception {
+        return createExecutor(mapPath, new ArrayList<>(), parentPath);
     }
 
     Executor createExecutor(String mapPath, FunctionLoader functionLoader) throws Exception {
@@ -90,6 +103,12 @@ public void doMapping(Path cwd, String mappingFiles, String output, String expec
         }
     }
 
+    /**
+     * This method executes a mapping, compares it to the expected out, and returns the used Executor.
+     * @param mapPath The path of the mapping file.
+     * @param outPath The path of the file with the expected output.
+     * @return The Executor used to execute the mapping.
+     */
     public Executor doMapping(String mapPath, String outPath) {
         try {
             Executor executor = this.createExecutor(mapPath);
@@ -103,6 +122,31 @@ public Executor doMapping(String mapPath, String outPath) {
         return null;
     }
 
+    /**
+     * This method executes a mapping, compares it to the expected out, and returns the used Executor.
+     * @param mapPath The path of the mapping file.
+     * @param outPath The path of the file with the expected output.
+     * @param parentPath The path of the folder where the Executor looks for files, such as CSV files.
+     * @return The Executor used to execute the mapping.
+     */
+    public Executor doMapping(String mapPath, String outPath, String parentPath) {
+        try {
+            Executor executor = this.createExecutor(mapPath, parentPath);
+            doMapping(executor, outPath);
+            return executor;
+        } catch (Exception e) {
+            logger.error(e.getMessage(), e);
+            fail();
+        }
+
+        return null;
+    }
+
+    /**
+     * This method executes a mapping and compares with the expected output.
+     * @param executor The Executor that is used to execute the mapping.
+     * @param outPath The path of the file with the expected output.
+     */
     void doMapping(Executor executor, String outPath) throws Exception {
         QuadStore result = executor.execute(null);
         result.removeDuplicates();
diff --git a/src/test/resources/test-cases/RMLTC0000-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0000-SPARQL/mapping.ttl
index ce80d44a..3ef5916d 100644
--- a/src/test/resources/test-cases/RMLTC0000-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0000-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://www.example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0001a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0001a-SPARQL/mapping.ttl
index f4ce9979..0c96c082 100644
--- a/src/test/resources/test-cases/RMLTC0001a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0001a-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://www.example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0001b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0001b-SPARQL/mapping.ttl
index f4ce9979..0c96c082 100644
--- a/src/test/resources/test-cases/RMLTC0001b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0001b-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://www.example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0002a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0002a-SPARQL/mapping.ttl
index e00fff6b..153c5a4e 100644
--- a/src/test/resources/test-cases/RMLTC0002a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0002a-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -44,4 +45,4 @@
     rr:predicateObjectMap [
     rr:predicate foaf:name ;
     rr:objectMap [ rml:reference "Name.value" ]
-    ].
\ No newline at end of file
+    ].
diff --git a/src/test/resources/test-cases/RMLTC0002b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0002b-SPARQL/mapping.ttl
index 1ec413a7..572cdc45 100644
--- a/src/test/resources/test-cases/RMLTC0002b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0002b-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -39,4 +40,4 @@
       rr:predicateObjectMap [
         rr:predicate foaf:name;
         rr:objectMap [ rml:reference "Name.value" ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0002g-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0002g-SPARQL/mapping.ttl
index fa004536..a6de6238 100644
--- a/src/test/resources/test-cases/RMLTC0002g-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0002g-SPARQL/mapping.ttl
@@ -38,4 +38,4 @@
         rr:predicateObjectMap [
           rr:predicate ex:id ;
           rr:objectMap [ rml:reference "IDs" ]
-        ].
\ No newline at end of file
+        ].
diff --git a/src/test/resources/test-cases/RMLTC0002h-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0002h-SPARQL/mapping.ttl
index 2661aa43..0da99c93 100644
--- a/src/test/resources/test-cases/RMLTC0002h-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0002h-SPARQL/mapping.ttl
@@ -37,4 +37,4 @@
         rr:predicateObjectMap [
           rr:predicate ex:id ;
           rr:objectMap [ rml:reference "IDs" ]
-        ].
\ No newline at end of file
+        ].
diff --git a/src/test/resources/test-cases/RMLTC0003c-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0003c-SPARQL/mapping.ttl
index 3d875c18..c017cd23 100644
--- a/src/test/resources/test-cases/RMLTC0003c-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0003c-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -42,4 +43,4 @@
           rr:template "{FirstName.value} {LastName.value}";
           rr:termType rr:Literal;
         ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0004a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0004a-SPARQL/mapping.ttl
index 38d352bd..de87246e 100644
--- a/src/test/resources/test-cases/RMLTC0004a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0004a-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0004b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0004b-SPARQL/mapping.ttl
index e2784ff2..a31697f9 100644
--- a/src/test/resources/test-cases/RMLTC0004b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0004b-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/>.
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0006a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0006a-SPARQL/mapping.ttl
index d5e651f3..8b64f1c2 100644
--- a/src/test/resources/test-cases/RMLTC0006a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0006a-SPARQL/mapping.ttl
@@ -39,4 +39,4 @@
       rr:predicateObjectMap [
         rr:predicateMap [ rr:constant ex:description ];
         rr:objectMap [ rr:constant "Bad Student"; ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0007a-JSON/mapping.ttl b/src/test/resources/test-cases/RMLTC0007a-JSON/mapping.ttl
index d2b86553..a64e94e8 100644
--- a/src/test/resources/test-cases/RMLTC0007a-JSON/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007a-JSON/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1> a rr:TriplesMap;
diff --git a/src/test/resources/test-cases/RMLTC0007a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007a-SPARQL/mapping.ttl
index b45b65e7..31f32961 100644
--- a/src/test/resources/test-cases/RMLTC0007a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007a-SPARQL/mapping.ttl
@@ -7,7 +7,8 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
-@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0007b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007b-SPARQL/mapping.ttl
index d0c00e0f..c89f0a28 100644
--- a/src/test/resources/test-cases/RMLTC0007b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007b-SPARQL/mapping.ttl
@@ -7,6 +7,8 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -45,4 +47,4 @@
       rr:predicateObjectMap [
         rr:predicate foaf:name;
         rr:objectMap [ rml:reference "FirstName.value" ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0007b-XML/mapping.ttl b/src/test/resources/test-cases/RMLTC0007b-XML/mapping.ttl
index 08703a34..31d58455 100644
--- a/src/test/resources/test-cases/RMLTC0007b-XML/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007b-XML/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1> a rr:TriplesMap;
diff --git a/src/test/resources/test-cases/RMLTC0007c-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007c-SPARQL/mapping.ttl
index 74f61419..d12df973 100644
--- a/src/test/resources/test-cases/RMLTC0007c-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007c-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -40,4 +41,4 @@
       rr:predicateObjectMap [
         rr:predicate foaf:name;
         rr:objectMap [ rml:reference "FirstName.value" ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0007d-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007d-SPARQL/mapping.ttl
index 15a1a72b..e7612b38 100644
--- a/src/test/resources/test-cases/RMLTC0007d-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007d-SPARQL/mapping.ttl
@@ -7,7 +7,8 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
-@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -50,4 +51,4 @@
       rr:predicateObjectMap [
         rr:predicate foaf:name;
         rr:objectMap [ rml:reference "FirstName.value" ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0007e-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007e-SPARQL/mapping.ttl
index f9171ba1..463add74 100644
--- a/src/test/resources/test-cases/RMLTC0007e-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007e-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -36,4 +37,4 @@
         rr:template "http://example.com/Student/{ID.value}/{FirstName.value}";
         rr:graph ex:PersonGraph ;
         rr:class foaf:Person
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0007f-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007f-SPARQL/mapping.ttl
index e4651680..ceffd5d4 100644
--- a/src/test/resources/test-cases/RMLTC0007f-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007f-SPARQL/mapping.ttl
@@ -7,7 +7,8 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
-@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
diff --git a/src/test/resources/test-cases/RMLTC0007g-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007g-SPARQL/mapping.ttl
index 89e64f62..9d54fc39 100644
--- a/src/test/resources/test-cases/RMLTC0007g-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007g-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -42,4 +43,4 @@
         rr:objectMap [
           rml:reference "FirstName.value"
         ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0007h-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0007h-SPARQL/mapping.ttl
index 80fb91cb..12608320 100644
--- a/src/test/resources/test-cases/RMLTC0007h-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0007h-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -42,4 +43,4 @@
         rr:objectMap [
           rml:reference "Name.value"
         ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0008a-JSON/mapping.ttl b/src/test/resources/test-cases/RMLTC0008a-JSON/mapping.ttl
index 2f972338..e7555251 100644
--- a/src/test/resources/test-cases/RMLTC0008a-JSON/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008a-JSON/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0008a-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008a-MySQL/mapping.ttl
index 255e44dc..550d8444 100644
--- a/src/test/resources/test-cases/RMLTC0008a-MySQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008a-MySQL/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0008a-PostgreSQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008a-PostgreSQL/mapping.ttl
index 2b3d658b..a75e65a0 100644
--- a/src/test/resources/test-cases/RMLTC0008a-PostgreSQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008a-PostgreSQL/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0008a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008a-SPARQL/mapping.ttl
index 8d40ef4e..d75cdd51 100644
--- a/src/test/resources/test-cases/RMLTC0008a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008a-SPARQL/mapping.ttl
@@ -7,6 +7,8 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -56,4 +58,4 @@
       rr:predicateObjectMap [
         rr:predicate ex:Sport ;
         rr:objectMap [ rml:reference "Sport.value" ]
-      ] .
\ No newline at end of file
+      ] .
diff --git a/src/test/resources/test-cases/RMLTC0008a-SQLServer/mapping.ttl b/src/test/resources/test-cases/RMLTC0008a-SQLServer/mapping.ttl
index 0e80e5e3..f28dacc9 100644
--- a/src/test/resources/test-cases/RMLTC0008a-SQLServer/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008a-SQLServer/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0008a-XML/mapping.ttl b/src/test/resources/test-cases/RMLTC0008a-XML/mapping.ttl
index e8ac6b61..0b7f30a4 100644
--- a/src/test/resources/test-cases/RMLTC0008a-XML/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008a-XML/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0008b-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC0008b-CSV/mapping.ttl
index 8b2b1c99..836348de 100644
--- a/src/test/resources/test-cases/RMLTC0008b-CSV/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008b-CSV/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 
 <TriplesMap2>
diff --git a/src/test/resources/test-cases/RMLTC0008b-JSON/mapping.ttl b/src/test/resources/test-cases/RMLTC0008b-JSON/mapping.ttl
index b7018ad7..5a721b6d 100644
--- a/src/test/resources/test-cases/RMLTC0008b-JSON/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008b-JSON/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 
 <TriplesMap2>
diff --git a/src/test/resources/test-cases/RMLTC0008b-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008b-MySQL/mapping.ttl
index 8205704d..b8c6ed75 100644
--- a/src/test/resources/test-cases/RMLTC0008b-MySQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008b-MySQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0008b-PostgreSQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008b-PostgreSQL/mapping.ttl
index 2885d662..f05d6b3f 100644
--- a/src/test/resources/test-cases/RMLTC0008b-PostgreSQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008b-PostgreSQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0008b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008b-SPARQL/mapping.ttl
index 3e293bc8..ddafbf92 100644
--- a/src/test/resources/test-cases/RMLTC0008b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008b-SPARQL/mapping.ttl
@@ -8,6 +8,8 @@
 @prefix activity: <http://example.com/activity/> .
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -85,4 +87,4 @@
 
     <RefObjectMap1>
       a rr:RefObjectMap;
-      rr:parentTriplesMap <TriplesMap2> .
\ No newline at end of file
+      rr:parentTriplesMap <TriplesMap2> .
diff --git a/src/test/resources/test-cases/RMLTC0008b-SQLServer/mapping.ttl b/src/test/resources/test-cases/RMLTC0008b-SQLServer/mapping.ttl
index a8dcdd90..589ca5f5 100644
--- a/src/test/resources/test-cases/RMLTC0008b-SQLServer/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008b-SQLServer/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0008c-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0008c-SPARQL/mapping.ttl
index 79f7bbd7..701e2900 100644
--- a/src/test/resources/test-cases/RMLTC0008c-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0008c-SPARQL/mapping.ttl
@@ -1,12 +1,13 @@
-@prefix rr: <http://www.w3.org/ns/r2rml#> .
-@prefix foaf: <http://xmlns.com/foaf/0.1/> .
-@prefix ex: <http://example.com/> .
-@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
-@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
-@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
-@prefix activity: <http://example.com/activity/> .
+@prefix rr:         <http://www.w3.org/ns/r2rml#> .
+@prefix foaf:       <http://xmlns.com/foaf/0.1/> .
+@prefix ex:         <http://example.com/> .
+@prefix xsd:        <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml:        <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql:         <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity:   <http://example.com/activity/> .
+@prefix d2rq:       <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix sd:         <http://www.w3.org/ns/sparql-service-description#> .
 @base <http://example.com/base/> .
-@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
 <#InputSPARQL>
     a sd:Service ;
diff --git a/src/test/resources/test-cases/RMLTC0009a-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-CSV/mapping.ttl
index 86f93ae9..d2fedc35 100644
--- a/src/test/resources/test-cases/RMLTC0009a-CSV/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-CSV/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0009a-JSON/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-JSON/mapping.ttl
index 8615e64b..20d59d52 100644
--- a/src/test/resources/test-cases/RMLTC0009a-JSON/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-JSON/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0009a-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-MySQL/mapping.ttl
index 172e9c03..3e103c4c 100644
--- a/src/test/resources/test-cases/RMLTC0009a-MySQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-MySQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0009a-PostgreSQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-PostgreSQL/mapping.ttl
index 35f28813..95e2ba81 100644
--- a/src/test/resources/test-cases/RMLTC0009a-PostgreSQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-PostgreSQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0009a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-SPARQL/mapping.ttl
index 482b44bd..3bd75e28 100644
--- a/src/test/resources/test-cases/RMLTC0009a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-SPARQL/mapping.ttl
@@ -1,12 +1,14 @@
-@prefix rr: <http://www.w3.org/ns/r2rml#> .
-@prefix foaf: <http://xmlns.com/foaf/0.1/> .
-@prefix ex: <http://example.com/> .
-@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
-@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
-@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
-@prefix activity: <http://example.com/activity/> .
+@prefix rr:         <http://www.w3.org/ns/r2rml#> .
+@prefix foaf:       <http://xmlns.com/foaf/0.1/> .
+@prefix ex:         <http://example.com/> .
+@prefix xsd:        <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml:        <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql:         <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity:   <http://example.com/activity/> .
+@prefix rdfs:       <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix d2rq:       <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix sd:         <http://www.w3.org/ns/sparql-service-description#> .
 @base <http://example.com/base/> .
-@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
 <#InputSPARQL1>
     a sd:Service ;
diff --git a/src/test/resources/test-cases/RMLTC0009a-SQLServer/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-SQLServer/mapping.ttl
index 4ca36f79..21399ba0 100644
--- a/src/test/resources/test-cases/RMLTC0009a-SQLServer/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-SQLServer/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0009a-XML/mapping.ttl b/src/test/resources/test-cases/RMLTC0009a-XML/mapping.ttl
index 50b32d48..1595b3be 100644
--- a/src/test/resources/test-cases/RMLTC0009a-XML/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009a-XML/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0009b-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-CSV/mapping.ttl
index 0bc35934..91253f04 100644
--- a/src/test/resources/test-cases/RMLTC0009b-CSV/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-CSV/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0009b-JSON/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-JSON/mapping.ttl
index fc8d1eba..8456985e 100644
--- a/src/test/resources/test-cases/RMLTC0009b-JSON/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-JSON/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0009b-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-MySQL/mapping.ttl
index 4f445248..d6c7c85e 100644
--- a/src/test/resources/test-cases/RMLTC0009b-MySQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-MySQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0009b-PostgreSQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-PostgreSQL/mapping.ttl
index ad2faeed..796b90fc 100644
--- a/src/test/resources/test-cases/RMLTC0009b-PostgreSQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-PostgreSQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0009b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-SPARQL/mapping.ttl
index d5fff23e..59929b0c 100644
--- a/src/test/resources/test-cases/RMLTC0009b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-SPARQL/mapping.ttl
@@ -1,12 +1,14 @@
-@prefix rr: <http://www.w3.org/ns/r2rml#> .
-@prefix foaf: <http://xmlns.com/foaf/0.1/> .
-@prefix ex: <http://example.com/> .
-@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
-@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
-@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
-@prefix activity: <http://example.com/activity/> .
+@prefix rr:         <http://www.w3.org/ns/r2rml#> .
+@prefix foaf:       <http://xmlns.com/foaf/0.1/> .
+@prefix ex:         <http://example.com/> .
+@prefix xsd:        <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml:        <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql:         <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity:   <http://example.com/activity/> .
+@prefix rdfs:       <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix d2rq:       <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix sd:         <http://www.w3.org/ns/sparql-service-description#> .
 @base <http://example.com/base/> .
-@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
 <#InputSPARQL1>
     a sd:Service ;
diff --git a/src/test/resources/test-cases/RMLTC0009b-SQLServer/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-SQLServer/mapping.ttl
index c0be7c88..d0eef0f8 100644
--- a/src/test/resources/test-cases/RMLTC0009b-SQLServer/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-SQLServer/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
diff --git a/src/test/resources/test-cases/RMLTC0009b-XML/mapping.ttl b/src/test/resources/test-cases/RMLTC0009b-XML/mapping.ttl
index 42349c92..7dfbea3b 100644
--- a/src/test/resources/test-cases/RMLTC0009b-XML/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0009b-XML/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix activity: <http://example.com/activity/> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0012a-MySQL/output.nq b/src/test/resources/test-cases/RMLTC0012a-MySQL/output.nq
index de57968a..10e4040a 100644
--- a/src/test/resources/test-cases/RMLTC0012a-MySQL/output.nq
+++ b/src/test/resources/test-cases/RMLTC0012a-MySQL/output.nq
@@ -2,3 +2,4 @@ _:Bob_Smith_30 <http://example.com/amount> "30"^^<http://www.w3.org/2001/XMLSche
 _:Bob_Smith_30 <http://xmlns.com/foaf/0.1/name> "Bob Smith" .
 _:Sue_Jones_20 <http://example.com/amount> "20"^^<http://www.w3.org/2001/XMLSchema#integer> .
 _:Sue_Jones_20 <http://xmlns.com/foaf/0.1/name> "Sue Jones" .
+
diff --git a/src/test/resources/test-cases/RMLTC0012a-PostgreSQL/output.nq b/src/test/resources/test-cases/RMLTC0012a-PostgreSQL/output.nq
index de57968a..10e4040a 100644
--- a/src/test/resources/test-cases/RMLTC0012a-PostgreSQL/output.nq
+++ b/src/test/resources/test-cases/RMLTC0012a-PostgreSQL/output.nq
@@ -2,3 +2,4 @@ _:Bob_Smith_30 <http://example.com/amount> "30"^^<http://www.w3.org/2001/XMLSche
 _:Bob_Smith_30 <http://xmlns.com/foaf/0.1/name> "Bob Smith" .
 _:Sue_Jones_20 <http://example.com/amount> "20"^^<http://www.w3.org/2001/XMLSchema#integer> .
 _:Sue_Jones_20 <http://xmlns.com/foaf/0.1/name> "Sue Jones" .
+
diff --git a/src/test/resources/test-cases/RMLTC0012a-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0012a-SPARQL/mapping.ttl
index a3db34b6..0ec54f97 100644
--- a/src/test/resources/test-cases/RMLTC0012a-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0012a-SPARQL/mapping.ttl
@@ -7,6 +7,7 @@
 @prefix sd:     <http://www.w3.org/ns/sparql-service-description#>.
 @prefix ex:     <http://example.com/> .
 @prefix hydra:  <http://www.w3.org/ns/hydra/core#> .
+@prefix foaf:   <http://xmlns.com/foaf/0.1/> .
 @base <http://example.com/base> .
 
 <#InputSPARQL>
@@ -47,4 +48,4 @@
         rr:objectMap    [
           rml:reference "amount.value";
         ]
-      ].
\ No newline at end of file
+      ].
diff --git a/src/test/resources/test-cases/RMLTC0012a-SQLServer/output.nq b/src/test/resources/test-cases/RMLTC0012a-SQLServer/output.nq
index de57968a..10e4040a 100644
--- a/src/test/resources/test-cases/RMLTC0012a-SQLServer/output.nq
+++ b/src/test/resources/test-cases/RMLTC0012a-SQLServer/output.nq
@@ -2,3 +2,4 @@ _:Bob_Smith_30 <http://example.com/amount> "30"^^<http://www.w3.org/2001/XMLSche
 _:Bob_Smith_30 <http://xmlns.com/foaf/0.1/name> "Bob Smith" .
 _:Sue_Jones_20 <http://example.com/amount> "20"^^<http://www.w3.org/2001/XMLSchema#integer> .
 _:Sue_Jones_20 <http://xmlns.com/foaf/0.1/name> "Sue Jones" .
+
diff --git a/src/test/resources/test-cases/RMLTC0012b-SPARQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0012b-SPARQL/mapping.ttl
index b2af38c8..38c6155f 100644
--- a/src/test/resources/test-cases/RMLTC0012b-SPARQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0012b-SPARQL/mapping.ttl
@@ -1,12 +1,13 @@
 @prefix rr: <http://www.w3.org/ns/r2rml#> .
-@prefix foaf: <http://xmlns.com/foaf/0.1/> .
-@prefix ex: <http://example.com/> .
-@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
-@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
-@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
-@prefix activity: <http://example.com/activity/> .
+@prefix foaf:       <http://xmlns.com/foaf/0.1/> .
+@prefix ex:         <http://example.com/> .
+@prefix xsd:        <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml:        <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql:         <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity:   <http://example.com/activity/> .
+@prefix d2rq:       <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix sd:         <http://www.w3.org/ns/sparql-service-description#> .
 @base <http://example.com/base/> .
-@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
 
 <#InputSPARQL1>
     a sd:Service ;
diff --git a/src/test/resources/test-cases/RMLTC0012e-MySQL/resource.sql b/src/test/resources/test-cases/RMLTC0012e-MySQL/resource.sql
index e1600c56..718792c7 100644
--- a/src/test/resources/test-cases/RMLTC0012e-MySQL/resource.sql
+++ b/src/test/resources/test-cases/RMLTC0012e-MySQL/resource.sql
@@ -6,9 +6,9 @@ CREATE TABLE IOUs (
       fname VARCHAR(20),
       lname VARCHAR(20),
       amount FLOAT);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30.0);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Sue', 'Jones', 20.0);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30.0);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Sue', 'Jones', 20);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30);
 
 CREATE TABLE Lives (
       fname VARCHAR(20),
diff --git a/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/output.nq b/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/output.nq
index f9a73fc5..caec8253 100644
--- a/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/output.nq
+++ b/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/output.nq
@@ -14,3 +14,4 @@ _:Sue_Jones_Madrid <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://exa
 _:Sue_Jones_Madrid <http://example.com/base/IOUs#fname> "Sue" .
 _:Sue_Jones_Madrid <http://example.com/base/IOUs#lname> "Jones" .
 _:Sue_Jones_Madrid <http://example.com/base/IOUs#city> "Madrid" .
+
diff --git a/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/resource.sql b/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/resource.sql
index d5589112..46e386f7 100644
--- a/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/resource.sql
+++ b/src/test/resources/test-cases/RMLTC0012e-PostgreSQL/resource.sql
@@ -5,9 +5,9 @@ CREATE TABLE IOUs (
       fname VARCHAR(20),
       lname VARCHAR(20),
       amount FLOAT);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30.0);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Sue', 'Jones', 20.0);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30.0);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Sue', 'Jones', 20);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30);
 
 CREATE TABLE Lives (
       fname VARCHAR(20),
diff --git a/src/test/resources/test-cases/RMLTC0012e-SQLServer/output.nq b/src/test/resources/test-cases/RMLTC0012e-SQLServer/output.nq
index 4b6c1b49..caec8253 100644
--- a/src/test/resources/test-cases/RMLTC0012e-SQLServer/output.nq
+++ b/src/test/resources/test-cases/RMLTC0012e-SQLServer/output.nq
@@ -1,11 +1,11 @@
-_:Bob_Smith_30.0 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.com/base/IOUs> .
-_:Bob_Smith_30.0 <http://example.com/base/IOUs#fname> "Bob" .
-_:Bob_Smith_30.0 <http://example.com/base/IOUs#lname> "Smith" .
-_:Bob_Smith_30.0 <http://example.com/base/IOUs#amount> "3.0E1"^^<http://www.w3.org/2001/XMLSchema#double> .
-_:Sue_Jones_20.0 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.com/base/IOUs> .
-_:Sue_Jones_20.0 <http://example.com/base/IOUs#fname> "Sue" .
-_:Sue_Jones_20.0 <http://example.com/base/IOUs#lname> "Jones" .
-_:Sue_Jones_20.0 <http://example.com/base/IOUs#amount> "2.0E1"^^<http://www.w3.org/2001/XMLSchema#double> .
+_:Bob_Smith_30 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.com/base/IOUs> .
+_:Bob_Smith_30 <http://example.com/base/IOUs#fname> "Bob" .
+_:Bob_Smith_30 <http://example.com/base/IOUs#lname> "Smith" .
+_:Bob_Smith_30 <http://example.com/base/IOUs#amount> "3.0E1"^^<http://www.w3.org/2001/XMLSchema#double> .
+_:Sue_Jones_20 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.com/base/IOUs> .
+_:Sue_Jones_20 <http://example.com/base/IOUs#fname> "Sue" .
+_:Sue_Jones_20 <http://example.com/base/IOUs#lname> "Jones" .
+_:Sue_Jones_20 <http://example.com/base/IOUs#amount> "2.0E1"^^<http://www.w3.org/2001/XMLSchema#double> .
 _:Bob_Smith_London <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.com/base/Lives> .
 _:Bob_Smith_London <http://example.com/base/IOUs#fname> "Bob" .
 _:Bob_Smith_London <http://example.com/base/IOUs#lname> "Smith" .
@@ -14,3 +14,4 @@ _:Sue_Jones_Madrid <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://exa
 _:Sue_Jones_Madrid <http://example.com/base/IOUs#fname> "Sue" .
 _:Sue_Jones_Madrid <http://example.com/base/IOUs#lname> "Jones" .
 _:Sue_Jones_Madrid <http://example.com/base/IOUs#city> "Madrid" .
+
diff --git a/src/test/resources/test-cases/RMLTC0012e-SQLServer/resource.sql b/src/test/resources/test-cases/RMLTC0012e-SQLServer/resource.sql
index f9180ce8..8fab5e6f 100644
--- a/src/test/resources/test-cases/RMLTC0012e-SQLServer/resource.sql
+++ b/src/test/resources/test-cases/RMLTC0012e-SQLServer/resource.sql
@@ -6,9 +6,9 @@ CREATE TABLE IOUs (
       fname VARCHAR(20),
       lname VARCHAR(20),
       amount FLOAT);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30.0);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Sue', 'Jones', 20.0);
-INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30.0);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Sue', 'Jones', 20);
+INSERT INTO IOUs (fname, lname, amount) VALUES ('Bob', 'Smith', 30);
 
 CREATE TABLE Lives (
       fname VARCHAR(20),
diff --git a/src/test/resources/test-cases/RMLTC0015a-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC0015a-CSV/mapping.ttl
index e42e2d0b..4b5ec259 100644
--- a/src/test/resources/test-cases/RMLTC0015a-CSV/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015a-CSV/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015a-JSON/mapping.ttl b/src/test/resources/test-cases/RMLTC0015a-JSON/mapping.ttl
index 77e47588..47405fd7 100644
--- a/src/test/resources/test-cases/RMLTC0015a-JSON/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015a-JSON/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015a-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0015a-MySQL/mapping.ttl
index 52c8202a..2074045c 100644
--- a/src/test/resources/test-cases/RMLTC0015a-MySQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015a-MySQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015a-PostgreSQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0015a-PostgreSQL/mapping.ttl
index b1be7019..b76862a7 100644
--- a/src/test/resources/test-cases/RMLTC0015a-PostgreSQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015a-PostgreSQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015a-SQLServer/mapping.ttl b/src/test/resources/test-cases/RMLTC0015a-SQLServer/mapping.ttl
index 7c3b8671..6c79f9fe 100644
--- a/src/test/resources/test-cases/RMLTC0015a-SQLServer/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015a-SQLServer/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015a-XML/mapping.ttl b/src/test/resources/test-cases/RMLTC0015a-XML/mapping.ttl
index 0457cc59..5677fe45 100644
--- a/src/test/resources/test-cases/RMLTC0015a-XML/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015a-XML/mapping.ttl
@@ -4,6 +4,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015b-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0015b-MySQL/mapping.ttl
index a470a707..5f70f31e 100644
--- a/src/test/resources/test-cases/RMLTC0015b-MySQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015b-MySQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015b-PostgreSQL/mapping.ttl b/src/test/resources/test-cases/RMLTC0015b-PostgreSQL/mapping.ttl
index 1954b473..b0f654ea 100644
--- a/src/test/resources/test-cases/RMLTC0015b-PostgreSQL/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015b-PostgreSQL/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0015b-SQLServer/mapping.ttl b/src/test/resources/test-cases/RMLTC0015b-SQLServer/mapping.ttl
index 8ed56590..b0f9124b 100644
--- a/src/test/resources/test-cases/RMLTC0015b-SQLServer/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0015b-SQLServer/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
 @prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
 @base <http://example.com/base/> .
 
 <TriplesMap1>
diff --git a/src/test/resources/test-cases/RMLTC0020a-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC0020a-CSV/mapping.ttl
index 58877c84..8eb9f19a 100644
--- a/src/test/resources/test-cases/RMLTC0020a-CSV/mapping.ttl
+++ b/src/test/resources/test-cases/RMLTC0020a-CSV/mapping.ttl
@@ -5,6 +5,7 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix rml: <http://semweb.mmlab.be/ns/rml#> .
 @prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
 
 @base <http://example.com/base/> .
 
diff --git a/src/test/resources/test-cases/RMLTC1018-CSV/input.csv b/src/test/resources/test-cases/RMLTC1018-CSV/input.csv
new file mode 100644
index 00000000..40beb64c
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1018-CSV/input.csv
@@ -0,0 +1,2 @@
+id
+test
\ No newline at end of file
diff --git a/src/test/resources/test-cases/RMLTC1018-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC1018-CSV/mapping.ttl
new file mode 100644
index 00000000..525e5bb6
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1018-CSV/mapping.ttl
@@ -0,0 +1,26 @@
+@prefix rr: <http://www.w3.org/ns/r2rml#> .
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+@prefix ex: <http://example.com/> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@base <http://example.com/base/> .
+
+<TriplesMap1> a rr:TriplesMap;
+    
+  rml:logicalSource [ 
+    rml:source "input.csv";
+    rml:referenceFormulation ql:CSV
+  ];
+
+  rr:subjectMap [ 
+    rr:template "http://example.com/{id}";
+  ];
+
+  rr:predicateObjectMap [ 
+    rr:predicate ex:test ;
+    rr:objectMap [
+      rr:termType rr:BlankNode
+    ]
+  ].
+
diff --git a/src/test/resources/test-cases/RMLTC1018-CSV/output.nq b/src/test/resources/test-cases/RMLTC1018-CSV/output.nq
new file mode 100644
index 00000000..0fe6b2eb
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1018-CSV/output.nq
@@ -0,0 +1 @@
+<http://example.com/test> <http://example.com/test> _:0 .
\ No newline at end of file
diff --git a/src/test/resources/test-cases/RMLTC1019-CSV/country_info.csv b/src/test/resources/test-cases/RMLTC1019-CSV/country_info.csv
new file mode 100644
index 00000000..559d014d
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1019-CSV/country_info.csv
@@ -0,0 +1,4 @@
+Country Code,Name,"""ISO 3166"""
+1,"Bolivia, Plurinational State of",BO
+2,Ireland,IE
+3,Saint Martin (French part),MF
diff --git a/src/test/resources/test-cases/RMLTC1019-CSV/mapping.ttl b/src/test/resources/test-cases/RMLTC1019-CSV/mapping.ttl
new file mode 100644
index 00000000..316594c3
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1019-CSV/mapping.ttl
@@ -0,0 +1,24 @@
+@prefix rr: <http://www.w3.org/ns/r2rml#> .
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+@prefix ex: <http://example.com/> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity: <http://example.com/activity/> .
+@base <http://example.com/base/> .
+@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+
+<TriplesMap1>
+  a rr:TriplesMap;
+
+  rml:logicalSource [
+    rml:source "country_info.csv";
+    rml:referenceFormulation ql:CSV
+  ];
+
+  rr:subjectMap [ rr:template "http://example.com/{Country Code}/{Name}" ];
+
+  rr:predicateObjectMap [
+    rr:predicate ex:code ;
+    rr:objectMap [ rr:template "\\{\\{\\{ {\"ISO 3166\"} \\}\\}\\}"; rr:termType rr:Literal]
+  ] .
diff --git a/src/test/resources/test-cases/RMLTC1019-CSV/output.nq b/src/test/resources/test-cases/RMLTC1019-CSV/output.nq
new file mode 100644
index 00000000..5c7e1080
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1019-CSV/output.nq
@@ -0,0 +1,4 @@
+<http://example.com/1/Bolivia%2C%20Plurinational%20State%20of> <http://example.com/code> "{{{ BO }}}" .
+<http://example.com/2/Ireland> <http://example.com/code> "{{{ IE }}}" .
+<http://example.com/3/Saint%20Martin%20%28French%20part%29> <http://example.com/code> "{{{ MF }}}" .
+
diff --git a/src/test/resources/test-cases/RMLTC1019-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC1019-MySQL/mapping.ttl
new file mode 100644
index 00000000..c5b2adca
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1019-MySQL/mapping.ttl
@@ -0,0 +1,31 @@
+@prefix rr: <http://www.w3.org/ns/r2rml#> .
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+@prefix ex: <http://example.com/> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity: <http://example.com/activity/> .
+@base <http://example.com/base/> .
+@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+
+<TriplesMap1>
+  a rr:TriplesMap;
+
+  rml:logicalSource [
+    rml:source <#DB_source>;
+    rr:sqlVersion rr:SQL2008;
+    rr:tableName "country_info";
+  ];
+
+  rr:subjectMap [ rr:template "http://example.com/{Country Code}/{Name}" ];
+
+  rr:predicateObjectMap [
+    rr:predicate ex:code ;
+    rr:objectMap [ rr:template "\\{\\{\\{ {\"ISO 3166\"} \\}\\}\\}"; rr:termType rr:Literal]
+  ] .
+
+<#DB_source> a d2rq:Database;
+  d2rq:jdbcDSN "CONNECTIONDSN"; 
+  d2rq:jdbcDriver "com.mysql.cj.jdbc.Driver";
+  d2rq:username "root";
+  d2rq:password "" .
diff --git a/src/test/resources/test-cases/RMLTC1019-MySQL/output.nq b/src/test/resources/test-cases/RMLTC1019-MySQL/output.nq
new file mode 100644
index 00000000..5c7e1080
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1019-MySQL/output.nq
@@ -0,0 +1,4 @@
+<http://example.com/1/Bolivia%2C%20Plurinational%20State%20of> <http://example.com/code> "{{{ BO }}}" .
+<http://example.com/2/Ireland> <http://example.com/code> "{{{ IE }}}" .
+<http://example.com/3/Saint%20Martin%20%28French%20part%29> <http://example.com/code> "{{{ MF }}}" .
+
diff --git a/src/test/resources/test-cases/RMLTC1019-MySQL/resource.sql b/src/test/resources/test-cases/RMLTC1019-MySQL/resource.sql
new file mode 100644
index 00000000..7a7aa74f
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1019-MySQL/resource.sql
@@ -0,0 +1,11 @@
+USE test;
+DROP TABLE IF EXISTS test.country_info;
+
+CREATE TABLE country_info (
+  `Country Code` INTEGER,
+  Name VARCHAR(100),
+  `ISO 3166` VARCHAR(10)
+);
+INSERT INTO country_info values ('1', 'Bolivia, Plurinational State of', 'BO');
+INSERT INTO country_info values ('2', 'Ireland', 'IE');
+INSERT INTO country_info values ('3', 'Saint Martin (French part)', 'MF');
diff --git a/src/test/resources/test-cases/RMLTC1020-MySQL/data.csv b/src/test/resources/test-cases/RMLTC1020-MySQL/data.csv
new file mode 100644
index 00000000..c6a85df9
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1020-MySQL/data.csv
@@ -0,0 +1,4 @@
+id,"""Country Code"""
+a,0
+b,1
+c,2
\ No newline at end of file
diff --git a/src/test/resources/test-cases/RMLTC1020-MySQL/mapping.ttl b/src/test/resources/test-cases/RMLTC1020-MySQL/mapping.ttl
new file mode 100644
index 00000000..22a8800d
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1020-MySQL/mapping.ttl
@@ -0,0 +1,47 @@
+@prefix rr: <http://www.w3.org/ns/r2rml#> .
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+@prefix ex: <http://example.com/> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
+@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@prefix activity: <http://example.com/activity/> .
+@base <http://example.com/base/> .
+@prefix d2rq: <http://www.wiwiss.fu-berlin.de/suhl/bizer/D2RQ/0.1#> .
+
+<TriplesMap1>
+  a rr:TriplesMap;
+
+  rml:logicalSource [
+    rml:source <#DB_source>;
+    rr:sqlVersion rr:SQL2008;
+    rr:tableName "country_info";
+  ];
+
+  rr:subjectMap [ rr:template "http://example.com/{Country Code}/" ];
+
+  rr:predicateObjectMap [
+      rr:predicate ex:country ;
+      rr:objectMap [
+        rr:parentTriplesMap <TriplesMap2>;
+        rr:joinCondition [
+          rr:parent "\"Country Code\"";
+          rr:child "Country Code"
+        ]
+      ]
+    ].
+
+<TriplesMap2>
+  a rr:TriplesMap;
+
+  rml:logicalSource [
+    rml:source "data.csv";
+    rml:referenceFormulation ql:CSV
+  ];
+
+  rr:subjectMap [ rr:template "http://example.com/person/{id}/" ].
+
+<#DB_source> a d2rq:Database;
+  d2rq:jdbcDSN "CONNECTIONDSN"; 
+  d2rq:jdbcDriver "com.mysql.cj.jdbc.Driver";
+  d2rq:username "root";
+  d2rq:password "" .
diff --git a/src/test/resources/test-cases/RMLTC1020-MySQL/output.nq b/src/test/resources/test-cases/RMLTC1020-MySQL/output.nq
new file mode 100644
index 00000000..dd024259
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1020-MySQL/output.nq
@@ -0,0 +1,2 @@
+<http://example.com/1/> <http://example.com/country> <http://example.com/person/b/>.
+<http://example.com/2/> <http://example.com/country> <http://example.com/person/c/>.
\ No newline at end of file
diff --git a/src/test/resources/test-cases/RMLTC1020-MySQL/resource.sql b/src/test/resources/test-cases/RMLTC1020-MySQL/resource.sql
new file mode 100644
index 00000000..7a7aa74f
--- /dev/null
+++ b/src/test/resources/test-cases/RMLTC1020-MySQL/resource.sql
@@ -0,0 +1,11 @@
+USE test;
+DROP TABLE IF EXISTS test.country_info;
+
+CREATE TABLE country_info (
+  `Country Code` INTEGER,
+  Name VARCHAR(100),
+  `ISO 3166` VARCHAR(10)
+);
+INSERT INTO country_info values ('1', 'Bolivia, Plurinational State of', 'BO');
+INSERT INTO country_info values ('2', 'Ireland', 'IE');
+INSERT INTO country_info values ('3', 'Saint Martin (French part)', 'MF');
