diff --git a/test-cases/RMLSTC0004a/Friends-NULL.csv b/test-cases/RMLSTC0004a/Friends-NULL.csv
index ce0c558..ab5f192 100644
--- a/test-cases/RMLSTC0004a/Friends-NULL.csv
+++ b/test-cases/RMLSTC0004a/Friends-NULL.csv
@@ -1,7 +1,7 @@
-id, name, age
-0, Monica Geller, 33
-1, Rachel Green, 34
-2, Joey Tribbiani, 35
-3, Chandler Bing, 36
-4, Ross Geller, 37
-5,,
+id;name;age
+0;Monica Geller;33
+1;Rachel Green;34
+2;Joey Tribbiani;35
+3;Chandler Bing;36
+4;Ross Geller;37
+5;;
diff --git a/test-cases/RMLSTC0004a/default.nq b/test-cases/RMLSTC0004a/default.nq
index d945676..93cbe17 100644
--- a/test-cases/RMLSTC0004a/default.nq
+++ b/test-cases/RMLSTC0004a/default.nq
@@ -8,3 +8,5 @@
 <http://example.org/3> <http://xmlns.com/foaf/0.1/name> "Chandler Bing" .
 <http://example.org/4> <http://xmlns.com/foaf/0.1/age> "37" .
 <http://example.org/4> <http://xmlns.com/foaf/0.1/name> "Ross Geller" .
+<http://example.org/5> <http://xmlns.com/foaf/0.1/age> "" .
+<http://example.org/5> <http://xmlns.com/foaf/0.1/name> "" .
diff --git a/test-cases/RMLSTC0004b/Friends-NULL.csv b/test-cases/RMLSTC0004b/Friends-NULL.csv
index ce0c558..ab5f192 100644
--- a/test-cases/RMLSTC0004b/Friends-NULL.csv
+++ b/test-cases/RMLSTC0004b/Friends-NULL.csv
@@ -1,7 +1,7 @@
-id, name, age
-0, Monica Geller, 33
-1, Rachel Green, 34
-2, Joey Tribbiani, 35
-3, Chandler Bing, 36
-4, Ross Geller, 37
-5,,
+id;name;age
+0;Monica Geller;33
+1;Rachel Green;34
+2;Joey Tribbiani;35
+3;Chandler Bing;36
+4;Ross Geller;37
+5;;
diff --git a/test-cases/RMLSTC0004c/Friends-NULL2.csv b/test-cases/RMLSTC0004c/Friends-NULL2.csv
index baeaeed..2bbf9a5 100644
--- a/test-cases/RMLSTC0004c/Friends-NULL2.csv
+++ b/test-cases/RMLSTC0004c/Friends-NULL2.csv
@@ -1,8 +1,8 @@
-id, name, age
-0, Monica Geller, 33
-1, Rachel Green, 34
-2, Joey Tribbiani, 35
-3, Chandler Bing, 36
-4, Ross Geller, 37
-5,,
-6,NULL,NULL
+id;name;age
+0;Monica Geller;33
+1;Rachel Green;34
+2;Joey Tribbiani;35
+3;Chandler Bing;36
+4;Ross Geller;37
+5;;
+6;NULL;NULL