diff --git a/data/carSimulationTBox.rdf b/data/carSimulationTBox.rdf
index ba2082d..efd4a66 100644
--- a/data/carSimulationTBox.rdf
+++ b/data/carSimulationTBox.rdf
@@ -3,38 +3,48 @@
     xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#">
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#Car">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarModel">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#Driver">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#Event">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarEvent">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
     <rdfs:subClassOf rdf:resource="http://example.org/carSim/carSimulationOntology#Event"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarAirbagEvent">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
     <rdfs:subClassOf rdf:resource="http://example.org/carSim/carSimulationOntology#CarEvent"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarStatusEvent">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
     <rdfs:subClassOf rdf:resource="http://example.org/carSim/carSimulationOntology#CarEvent"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarUserEvent">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
     <rdfs:subClassOf rdf:resource="http://example.org/carSim/carSimulationOntology#CarEvent"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarTakenEvent">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
     <rdfs:subClassOf rdf:resource="http://example.org/carSim/carSimulationOntology#CarUserEvent"/>
   </rdf:Description>
 
   <rdf:Description rdf:about="http://example.org/carSim/carSimulationOntology#CarReturnedEvent">
+    <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
     <rdfs:subClassOf rdf:resource="http://example.org/carSim/carSimulationOntology#CarUserEvent"/>
   </rdf:Description>
 
diff --git a/data/rdfs.rules b/data/rdfs.rules
index be5a1cf..7115add 100644
--- a/data/rdfs.rules
+++ b/data/rdfs.rules
@@ -51,17 +51,15 @@
 #------------------------------------------------------------------
 # RDFS Closure rules
 #------------------------------------------------------------------
-
 # This one could be omitted since the results are not really very interesting!
 [rdf1and4: (?x ?p ?y) -> (?p rdf:type rdf:Property), (?x rdf:type rdfs:Resource), (?y rdf:type rdfs:Resource)]
 [rdfs7b: (?a rdf:type rdfs:Class) -> (?a rdfs:subClassOf rdfs:Resource)] 
-
-[rdfs2:  (?x ?p ?y), (?p rdfs:domain ?c) -> (?x rdf:type ?c)] 
-[rdfs3:  (?x ?p ?y), (?p rdfs:range ?c) -> (?y rdf:type ?c)] 
+[rdfs2: (?x ?p ?y), (?p rdfs:domain ?c) -> (?x rdf:type ?c)] 
+[rdfs3: (?x ?p ?y), (?p rdfs:range ?c) -> (?y rdf:type ?c)] 
 [rdfs5a: (?a rdfs:subPropertyOf ?b), (?b rdfs:subPropertyOf ?c) -> (?a rdfs:subPropertyOf ?c)] 
 [rdfs5b: (?a rdf:type rdf:Property) -> (?a rdfs:subPropertyOf ?a)] 
-[rdfs6:  (?a ?p ?b), (?p rdfs:subPropertyOf ?q) -> (?a ?q ?b)] 
-[rdfs7:  (?a rdf:type rdfs:Class) -> (?a rdfs:subClassOf ?a)]
-[rdfs8:  (?a rdfs:subClassOf ?b), (?b rdfs:subClassOf ?c) -> (?a rdfs:subClassOf ?c)] 
-[rdfs9:  (?x rdfs:subClassOf ?y), (?a rdf:type ?x) -> (?a rdf:type ?y)] 
+[rdfs6: (?a ?p ?b), (?p rdfs:subPropertyOf ?q) -> (?a ?q ?b)] 
+[rdfs7: (?a rdf:type rdfs:Class) -> (?a rdfs:subClassOf ?a)]
+[rdfs8: (?a rdfs:subClassOf ?b), (?b rdfs:subClassOf ?c) -> (?a rdfs:subClassOf ?c)] 
+[rdfs9: (?x rdfs:subClassOf ?y), (?a rdf:type ?x) -> (?a rdf:type ?y)] 
 [rdfs10: (?x rdf:type rdfs:ContainerMembershipProperty) -> (?x rdfs:subPropertyOf rdfs:member)] 
diff --git a/src/main/java/lu/jpt/csparqlproject/Main.java b/src/main/java/lu/jpt/csparqlproject/Main.java
index cb9fe91..6a1a922 100644
--- a/src/main/java/lu/jpt/csparqlproject/Main.java
+++ b/src/main/java/lu/jpt/csparqlproject/Main.java
@@ -30,6 +30,7 @@ public class Main {
 		Main.prefixManager = new PrefixManager();
 		// Register generic prefixes
 		Main.prefixManager.registerPrefix("rdf", "http://www.w3.org/1999/02/22-rdf-syntax-ns#");
+		Main.prefixManager.registerPrefix("rdfs", "http://www.w3.org/2000/01/rdf-schema#");
 		Main.prefixManager.registerPrefix("xsd", "http://www.w3.org/2001/XMLSchema#");
 		Main.prefixManager.registerPrefix("f", "http://larkc.eu/csparql/sparql/jena/ext#");