diff --git a/RDFSharp/Model/RDFNamespaceRegister.cs b/RDFSharp/Model/RDFNamespaceRegister.cs
index 9b04895dd..1eb8bf913 100644
--- a/RDFSharp/Model/RDFNamespaceRegister.cs
+++ b/RDFSharp/Model/RDFNamespaceRegister.cs
@@ -94,13 +94,15 @@ static RDFNamespaceRegister()
             AddNamespace(new RDFNamespace(RDFVocabulary.DC.DCTYPE.PREFIX, RDFVocabulary.DC.DCTYPE.BASE_URI));
             //foaf
             AddNamespace(new RDFNamespace(RDFVocabulary.FOAF.PREFIX, RDFVocabulary.FOAF.BASE_URI));
+            //earl
+            AddNamespace(new RDFNamespace(RDFVocabulary.EARL.PREFIX, RDFVocabulary.EARL.BASE_URI));
             //geo
             AddNamespace(new RDFNamespace(RDFVocabulary.GEO.PREFIX, RDFVocabulary.GEO.BASE_URI));
-            //skos
-            AddNamespace(new RDFNamespace(RDFVocabulary.SKOS.PREFIX, RDFVocabulary.SKOS.BASE_URI));
-            AddNamespace(new RDFNamespace(RDFVocabulary.SKOS.SKOSXL.PREFIX, RDFVocabulary.SKOS.SKOSXL.BASE_URI));
             //sioc
             AddNamespace(new RDFNamespace(RDFVocabulary.SIOC.PREFIX, RDFVocabulary.SIOC.BASE_URI));
+            //skos
+            AddNamespace(new RDFNamespace(RDFVocabulary.SKOS.PREFIX, RDFVocabulary.SKOS.BASE_URI));
+            AddNamespace(new RDFNamespace(RDFVocabulary.SKOS.SKOSXL.PREFIX, RDFVocabulary.SKOS.SKOSXL.BASE_URI));            
             #endregion
         }
         #endregion
diff --git a/RDFSharp/Model/Vocabularies/EARL.cs b/RDFSharp/Model/Vocabularies/EARL.cs
new file mode 100644
index 000000000..6d71c56a7
--- /dev/null
+++ b/RDFSharp/Model/Vocabularies/EARL.cs
@@ -0,0 +1,219 @@
+/*
+   Copyright 2012-2020 Marco De Salvo
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+using System;
+
+namespace RDFSharp.Model
+{
+    /// <summary>
+    /// RDFVocabulary is an helper for handy usage of supported RDF vocabularies.
+    /// </summary>
+    public static partial class RDFVocabulary
+    {
+        #region EARL
+        /// <summary>
+        /// EARL represents the Evaluation-And-Report-Language vocabulary.
+        /// </summary>
+        public static class EARL
+        {
+
+            #region Properties
+            /// <summary>
+            /// earl
+            /// </summary>
+            public static readonly String PREFIX = "earl";
+
+            /// <summary>
+            /// http://www.w3.org/ns/earl#
+            /// </summary>
+            public static readonly String BASE_URI = "http://www.w3.org/ns/earl#";
+
+            /// <summary>
+            /// earl:assertedBy
+            /// </summary>
+            public static readonly RDFResource ASSERTED_BY = new RDFResource(EARL.BASE_URI + "assertedBy");
+
+            /// <summary>
+            /// earl:Assertion
+            /// </summary>
+            public static readonly RDFResource ASSERTION = new RDFResource(EARL.BASE_URI + "Assertion");
+
+            /// <summary>
+            /// earl:Assertor
+            /// </summary>
+            public static readonly RDFResource ASSERTOR = new RDFResource(EARL.BASE_URI + "Assertor");
+
+            /// <summary>
+            /// earl:automatic
+            /// </summary>
+            public static readonly RDFResource AUTOMATIC = new RDFResource(EARL.BASE_URI + "automatic");
+
+            /// <summary>
+            /// earl:cantTell
+            /// </summary>
+            public static readonly RDFResource CANT_TELL = new RDFResource(EARL.BASE_URI + "cantTell");
+
+            /// <summary>
+            /// earl:CannotTell
+            /// </summary>
+            public static readonly RDFResource CANNOT_TELL = new RDFResource(EARL.BASE_URI + "CannotTell");
+
+            /// <summary>
+            /// earl:Fail
+            /// </summary>
+            public static readonly RDFResource FAIL = new RDFResource(EARL.BASE_URI + "Fail");
+
+            /// <summary>
+            /// earl:failed
+            /// </summary>
+            public static readonly RDFResource FAILED = new RDFResource(EARL.BASE_URI + "failed");
+
+            /// <summary>
+            /// earl:info
+            /// </summary>
+            public static readonly RDFResource INFO = new RDFResource(EARL.BASE_URI + "info");
+
+            /// <summary>
+            /// earl:inapplicable
+            /// </summary>
+            public static readonly RDFResource INAPPLICABLE = new RDFResource(EARL.BASE_URI + "inapplicable");
+
+            /// <summary>
+            /// earl:mainAssertor
+            /// </summary>
+            public static readonly RDFResource MAIN_ASSERTOR = new RDFResource(EARL.BASE_URI + "mainAssertor");
+
+            /// <summary>
+            /// earl:manual
+            /// </summary>
+            public static readonly RDFResource MANUAL = new RDFResource(EARL.BASE_URI + "manual");
+
+            /// <summary>
+            /// earl:mode
+            /// </summary>
+            public static readonly RDFResource MODE = new RDFResource(EARL.BASE_URI + "mode");
+
+            /// <summary>
+            /// earl:NotApplicable
+            /// </summary>
+            public static readonly RDFResource NOT_APPLICABLE = new RDFResource(EARL.BASE_URI + "NotApplicable");
+
+            /// <summary>
+            /// earl:NotTested
+            /// </summary>
+            public static readonly RDFResource NOT_TESTED = new RDFResource(EARL.BASE_URI + "NotTested");
+
+            /// <summary>
+            /// earl:outcome
+            /// </summary>
+            public static readonly RDFResource OUTCOME = new RDFResource(EARL.BASE_URI + "outcome");
+
+            /// <summary>
+            /// earl:OutcomeValue
+            /// </summary>
+            public static readonly RDFResource OUTCOME_VALUE = new RDFResource(EARL.BASE_URI + "OutcomeValue");
+
+            /// <summary>
+            /// earl:Pass
+            /// </summary>
+            public static readonly RDFResource PASS = new RDFResource(EARL.BASE_URI + "Pass");
+
+            /// <summary>
+            /// earl:passed
+            /// </summary>
+            public static readonly RDFResource PASSED = new RDFResource(EARL.BASE_URI + "passed");
+
+            /// <summary>
+            /// earl:pointer
+            /// </summary>
+            public static readonly RDFResource POINTER = new RDFResource(EARL.BASE_URI + "pointer");
+
+            /// <summary>
+            /// earl:result
+            /// </summary>
+            public static readonly RDFResource RESULT = new RDFResource(EARL.BASE_URI + "result");
+
+            /// <summary>
+            /// earl:semiAuto
+            /// </summary>
+            public static readonly RDFResource SEMIAUTO = new RDFResource(EARL.BASE_URI + "semiAuto");
+
+            /// <summary>
+            /// earl:Software
+            /// </summary>
+            public static readonly RDFResource SOFTWARE = new RDFResource(EARL.BASE_URI + "Software");
+
+            /// <summary>
+            /// earl:subject
+            /// </summary>
+            public static readonly RDFResource SUBJECT = new RDFResource(EARL.BASE_URI + "subject");
+
+            /// <summary>
+            /// earl:test
+            /// </summary>
+            public static readonly RDFResource TEST = new RDFResource(EARL.BASE_URI + "test");
+
+            /// <summary>
+            /// earl:TestCase
+            /// </summary>
+            public static readonly RDFResource TEST_CASE = new RDFResource(EARL.BASE_URI + "TestCase");
+
+            /// <summary>
+            /// earl:TestCriterion
+            /// </summary>
+            public static readonly RDFResource TEST_CRITERION = new RDFResource(EARL.BASE_URI + "TestCriterion");
+
+            /// <summary>
+            /// earl:TestMode
+            /// </summary>
+            public static readonly RDFResource TEST_MODE = new RDFResource(EARL.BASE_URI + "TestMode");
+
+            /// <summary>
+            /// earl:TestRequirement
+            /// </summary>
+            public static readonly RDFResource TEST_REQUIREMENT = new RDFResource(EARL.BASE_URI + "TestRequirement");
+
+            /// <summary>
+            /// earl:TestResult
+            /// </summary>
+            public static readonly RDFResource TEST_RESULT = new RDFResource(EARL.BASE_URI + "TestResult");
+
+            /// <summary>
+            /// earl:TestSubject
+            /// </summary>
+            public static readonly RDFResource TEST_SUBJECT = new RDFResource(EARL.BASE_URI + "TestSubject");
+
+            /// <summary>
+            /// earl:undisclosed
+            /// </summary>
+            public static readonly RDFResource UNDISCLOSED = new RDFResource(EARL.BASE_URI + "undisclosed");
+
+            /// <summary>
+            /// earl:unknownMode
+            /// </summary>
+            public static readonly RDFResource UNKNOWN_MODE = new RDFResource(EARL.BASE_URI + "unknownMode");
+
+            /// <summary>
+            /// earl:untested
+            /// </summary>
+            public static readonly RDFResource UNTESTED = new RDFResource(EARL.BASE_URI + "untested");
+
+            #endregion
+
+        }
+        #endregion
+    }
+}
\ No newline at end of file
diff --git a/RDFSharp/Semantics/LinkedData/DC/RDFDCOntology.cs b/RDFSharp/Semantics/LinkedData/DC/RDFDCOntology.cs
index ece5d8208..156f55c05 100644
--- a/RDFSharp/Semantics/LinkedData/DC/RDFDCOntology.cs
+++ b/RDFSharp/Semantics/LinkedData/DC/RDFDCOntology.cs
@@ -42,7 +42,7 @@ static RDFDCOntology()
             #region Declarations
 
             #region Ontology
-            Instance = new RDFOntology(new RDFResource("https://rdfsharp.codeplex.com/semantics/dc#"));
+            Instance = new RDFOntology(new RDFResource(RDFVocabulary.DC.BASE_URI));
             #endregion
 
             #region Classes
diff --git a/RDFSharp/Semantics/LinkedData/EARL/RDFEARLOntology.cs b/RDFSharp/Semantics/LinkedData/EARL/RDFEARLOntology.cs
new file mode 100644
index 000000000..47cf6ef4f
--- /dev/null
+++ b/RDFSharp/Semantics/LinkedData/EARL/RDFEARLOntology.cs
@@ -0,0 +1,159 @@
+/*
+   Copyright 2015-2020 Marco De Salvo
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+using RDFSharp.Model;
+
+namespace RDFSharp.Semantics
+{
+
+    /// <summary>
+    /// RDFEARLOntology represents an OWL-DL ontology implementation of EARL vocabulary
+    /// </summary>
+    public static class RDFEARLOntology
+    {
+
+        #region Properties
+        /// <summary>
+        /// Singleton instance of the EARL ontology
+        /// </summary>
+        public static RDFOntology Instance { get; internal set; }
+        #endregion
+
+        #region Ctors
+        /// <summary>
+        /// Default-ctor to initialize the EARL ontology
+        /// </summary>
+        static RDFEARLOntology()
+        {
+
+            #region Declarations
+
+            #region Ontology
+            Instance = new RDFOntology(new RDFResource(RDFVocabulary.EARL.BASE_URI));
+            #endregion
+
+            #region Classes
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.ASSERTION.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.ASSERTOR.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.CANNOT_TELL.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.FAIL.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.NOT_APPLICABLE.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.NOT_TESTED.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.PASS.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.SOFTWARE.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.TEST_CASE.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.TEST_CRITERION.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.TEST_MODE.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.TEST_REQUIREMENT.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.TEST_RESULT.ToRDFOntologyClass());
+            Instance.Model.ClassModel.AddClass(RDFVocabulary.EARL.TEST_SUBJECT.ToRDFOntologyClass());
+
+            //OWL-DL Completeness
+            Instance.Model.ClassModel.AddClass(new RDFOntologyClass(new RDFResource("http://usefulinc.com/ns/doap#Project")));
+            Instance.Model.ClassModel.AddClass(new RDFOntologyClass(new RDFResource("http://www.w3.org/2009/pointers#Pointer")));
+            #endregion
+
+            #region Properties
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.ASSERTED_BY.ToRDFOntologyObjectProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.INFO.ToRDFOntologyDatatypeProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.MAIN_ASSERTOR.ToRDFOntologyObjectProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.MODE.ToRDFOntologyObjectProperty());            
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.OUTCOME.ToRDFOntologyObjectProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.POINTER.ToRDFOntologyObjectProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.RESULT.ToRDFOntologyObjectProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.SUBJECT.ToRDFOntologyObjectProperty());
+            Instance.Model.PropertyModel.AddProperty(RDFVocabulary.EARL.TEST.ToRDFOntologyObjectProperty());
+            #endregion
+
+            #region Facts
+            Instance.Data.AddFact(RDFVocabulary.EARL.AUTOMATIC.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.CANT_TELL.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.INAPPLICABLE.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.FAILED.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.MANUAL.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.PASSED.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.SEMIAUTO.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.UNDISCLOSED.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.UNKNOWN_MODE.ToRDFOntologyFact());
+            Instance.Data.AddFact(RDFVocabulary.EARL.UNTESTED.ToRDFOntologyFact());
+            #endregion
+
+            #endregion
+
+            #region Taxonomies
+
+            #region ClassModel
+
+            //SubClassOf
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_REQUIREMENT.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_CRITERION.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_CASE.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_CRITERION.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.PASS.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.FAIL.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.CANNOT_TELL.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.NOT_APPLICABLE.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.NOT_TESTED.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToString()));
+            Instance.Model.ClassModel.AddSubClassOfRelation(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.SOFTWARE.ToString()), Instance.Model.ClassModel.SelectClass("http://usefulinc.com/ns/doap#Project"));
+
+            #endregion
+
+            #region PropertyModel
+
+            //Domain/Range
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.ASSERTED_BY.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTION.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.ASSERTED_BY.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTOR.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.SUBJECT.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTION.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.SUBJECT.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_SUBJECT.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.TEST.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTION.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.TEST.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_CRITERION.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.RESULT.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTION.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.RESULT.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_RESULT.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.MODE.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTION.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.MODE.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_MODE.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.MAIN_ASSERTOR.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTOR.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.MAIN_ASSERTOR.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.ASSERTOR.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.OUTCOME.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_RESULT.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.OUTCOME.ToString()).SetRange(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.OUTCOME_VALUE.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.POINTER.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_RESULT.ToString()));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.POINTER.ToString()).SetRange(Instance.Model.ClassModel.SelectClass("http://www.w3.org/2009/pointers#Pointer"));
+            Instance.Model.PropertyModel.SelectProperty(RDFVocabulary.EARL.INFO.ToString()).SetDomain(Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_RESULT.ToString()));
+
+            #endregion
+
+            #region Data
+
+            //ClassType
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.AUTOMATIC.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_MODE.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.MANUAL.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_MODE.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.SEMIAUTO.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_MODE.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.UNDISCLOSED.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_MODE.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.UNKNOWN_MODE.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.TEST_MODE.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.PASSED.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.PASS.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.FAILED.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.FAIL.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.CANT_TELL.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.CANNOT_TELL.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.INAPPLICABLE.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.NOT_APPLICABLE.ToString()));
+            Instance.Data.AddClassTypeRelation(Instance.Data.SelectFact(RDFVocabulary.EARL.UNTESTED.ToString()), Instance.Model.ClassModel.SelectClass(RDFVocabulary.EARL.NOT_TESTED.ToString()));
+
+            #endregion
+
+            #endregion
+
+        }
+        #endregion
+
+    }
+
+}
\ No newline at end of file
diff --git a/RDFSharp/Semantics/LinkedData/FOAF/RDFFOAFOntology.cs b/RDFSharp/Semantics/LinkedData/FOAF/RDFFOAFOntology.cs
index 8d3541e19..831b2c1eb 100644
--- a/RDFSharp/Semantics/LinkedData/FOAF/RDFFOAFOntology.cs
+++ b/RDFSharp/Semantics/LinkedData/FOAF/RDFFOAFOntology.cs
@@ -43,7 +43,7 @@ static RDFFOAFOntology()
             #region Declarations
 
             #region Ontology
-            Instance = new RDFOntology(new RDFResource("https://rdfsharp.codeplex.com/semantics/foaf#"));
+            Instance = new RDFOntology(new RDFResource(RDFVocabulary.FOAF.BASE_URI));
             #endregion
 
             #region Classes
diff --git a/RDFSharp/Semantics/LinkedData/GEO/RDFGEOOntology.cs b/RDFSharp/Semantics/LinkedData/GEO/RDFGEOOntology.cs
index 642a54275..af9d95b26 100644
--- a/RDFSharp/Semantics/LinkedData/GEO/RDFGEOOntology.cs
+++ b/RDFSharp/Semantics/LinkedData/GEO/RDFGEOOntology.cs
@@ -42,7 +42,7 @@ static RDFGEOOntology()
             #region Declarations
 
             #region Ontology
-            Instance = new RDFOntology(new RDFResource("https://rdfsharp.codeplex.com/semantics/geo#"));
+            Instance = new RDFOntology(new RDFResource(RDFVocabulary.GEO.BASE_URI));
             #endregion
 
             #region Classes
diff --git a/RDFSharp/Semantics/LinkedData/SIOC/RDFSIOCOntology.cs b/RDFSharp/Semantics/LinkedData/SIOC/RDFSIOCOntology.cs
index c71ae0f16..2892510f7 100644
--- a/RDFSharp/Semantics/LinkedData/SIOC/RDFSIOCOntology.cs
+++ b/RDFSharp/Semantics/LinkedData/SIOC/RDFSIOCOntology.cs
@@ -42,7 +42,7 @@ static RDFSIOCOntology()
             #region Declarations
 
             #region Ontology
-            Instance = new RDFOntology(new RDFResource("https://rdfsharp.codeplex.com/semantics/sioc#"));
+            Instance = new RDFOntology(new RDFResource(RDFVocabulary.SIOC.BASE_URI));
             #endregion
 
             #region Classes
diff --git a/RDFSharp/Semantics/LinkedData/SKOS/RDFSKOSOntology.cs b/RDFSharp/Semantics/LinkedData/SKOS/RDFSKOSOntology.cs
index 844ede045..1d3c3984d 100644
--- a/RDFSharp/Semantics/LinkedData/SKOS/RDFSKOSOntology.cs
+++ b/RDFSharp/Semantics/LinkedData/SKOS/RDFSKOSOntology.cs
@@ -43,7 +43,7 @@ static RDFSKOSOntology()
             #region Declarations
 
             #region Ontology
-            Instance = new RDFOntology(new RDFResource("http://www.w3.org/TR/skos-reference/skos-owl1-dl.rdf"));
+            Instance = new RDFOntology(new RDFResource(RDFVocabulary.SKOS.BASE_URI));
             #endregion
 
             #region Classes