diff --git a/.classpath b/.classpath
index 8131be0..e914f35 100644
--- a/.classpath
+++ b/.classpath
@@ -29,5 +29,10 @@
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
+	<classpathentry excluding="**" kind="src" output="target/classes" path="src/main/resources">
+		<attributes>
+			<attribute name="maven.pomderived" value="true"/>
+		</attributes>
+	</classpathentry>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>
diff --git a/src/main/java/org/gcube/informationsystem/utils/documentation/generator/ClassesDiscoveryGenerator.java b/src/main/java/org/gcube/informationsystem/utils/documentation/generator/ClassesDiscoveryGenerator.java
index c5c64d5..e09344b 100644
--- a/src/main/java/org/gcube/informationsystem/utils/documentation/generator/ClassesDiscoveryGenerator.java
+++ b/src/main/java/org/gcube/informationsystem/utils/documentation/generator/ClassesDiscoveryGenerator.java
@@ -54,7 +54,11 @@ public class ClassesDiscoveryGenerator extends Generator {
 	}
 	
 	protected <E extends Element> void  discover(AccessType at, Package[] packages) throws Exception {
-		ElementSpecilizationDiscovery<E> discovery = new ElementSpecilizationDiscovery<>(at.getTypeClass());
+		/*
+		 * I need to get all types also the types defined in IS Model
+		 * to properly support the specilizations if any
+		 */
+		ElementSpecilizationDiscovery<E> discovery = new ElementSpecilizationDiscovery<>(at.getTypeClass(), true);
 		if(Objects.nonNull(packages)) {
 			Arrays.stream(packages).forEach(p -> discovery.addPackage(p));
 		}
diff --git a/src/main/java/org/gcube/informationsystem/utils/documentation/generator/TreeGenerator.java b/src/main/java/org/gcube/informationsystem/utils/documentation/generator/TreeGenerator.java
index ea3a32d..1265305 100644
--- a/src/main/java/org/gcube/informationsystem/utils/documentation/generator/TreeGenerator.java
+++ b/src/main/java/org/gcube/informationsystem/utils/documentation/generator/TreeGenerator.java
@@ -73,7 +73,7 @@ public class TreeGenerator extends Generator {
 	}
 	
 	public void elaborateTree(final AccessType at, Tree tree, final File file) throws Exception {
-		logger.debug("Going to elaborate the following type tree\n{}", tree.toString());
+		logger.info("Going to elaborate the following type tree\n{}", tree.toString());
 		
 		NodeElaborator documentationNE = new NodeElaborator() {
 			
@@ -131,9 +131,6 @@ public class TreeGenerator extends Generator {
 		File is = getFile(IS_MODEL_FILENAME, true);
 		File file = null;
 		
-		Tree resourcesTree = types.get(AccessType.RESOURCE);
-		createUsageKnowledge(resourcesTree);
-		
 		for(AccessType at : accessTypes) {
 			Type type = TypeMapper.createTypeDefinition(at.getTypeClass());
 			writeTypeToFile(type, is);
diff --git a/src/main/java/org/gcube/informationsystem/utils/documentation/knowledge/Tree.java b/src/main/java/org/gcube/informationsystem/utils/documentation/knowledge/Tree.java
index 77ac2a9..eed8111 100644
--- a/src/main/java/org/gcube/informationsystem/utils/documentation/knowledge/Tree.java
+++ b/src/main/java/org/gcube/informationsystem/utils/documentation/knowledge/Tree.java
@@ -3,7 +3,9 @@ package org.gcube.informationsystem.utils.documentation.knowledge;
 import java.util.HashMap;
 import java.util.Set;
 
+import org.gcube.informationsystem.base.reference.AccessType;
 import org.gcube.informationsystem.types.reference.Type;
+import org.gcube.informationsystem.types.reference.entities.ResourceType;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
@@ -26,20 +28,36 @@ public class Tree {
 		this.allowMultipleInheritance = allowMultipleInheritance;
 	}
 	
-	public void addNode(Type t) {
-		if(root.getType().getName().compareTo(t.getName())==0) {
+	public void createUsageKnowledge(Type type) {
+		if(type.getAccessType() != AccessType.RESOURCE) {
+			return;
+		}
+		ResourceType rt = (ResourceType) type;
+		UsageKnowledge fk = UsageKnowledge.getFacetKnowledge();
+		fk.addAll(rt.getFacets());
+		UsageKnowledge rk = UsageKnowledge.getResourceKnowledge();
+		rk.addAll(rt.getResources()); 
+	}
+	
+	public void addNode(Type type) {
+		if(root.getType().getName().compareTo(type.getName())==0) {
 			// Root has been already added
 			return;
 		}
-		Set<String> superClasses = t.getSuperClasses();
+		
+		createUsageKnowledge(type);
+		
+		Set<String> superClasses = type.getSuperClasses();
+		
+		String name = type.getName();
 		for(String superClass : superClasses) {
 			Node parent = locate.get(superClass);
 			if(parent==null) {
-				throw new RuntimeException("I can find parent Node for " + t.getName() + ". Missing parent is " + superClass);
+				throw new RuntimeException("I can find parent Node for " + name + ". Missing parent is " + superClass);
 			}
-			Node node = new Node(t);
+			Node node = new Node(type);
 			parent.addChild(node);
-			locate.put(t.getName(), node);
+			locate.put(name, node);
 			if(!allowMultipleInheritance) {
 				return;
 			}
diff --git a/src/main/java/org/gcube/informationsystem/utils/documentation/model/entities/ResourceDocumentationGenerator.java b/src/main/java/org/gcube/informationsystem/utils/documentation/model/entities/ResourceDocumentationGenerator.java
index f22a159..b0f3ba0 100644
--- a/src/main/java/org/gcube/informationsystem/utils/documentation/model/entities/ResourceDocumentationGenerator.java
+++ b/src/main/java/org/gcube/informationsystem/utils/documentation/model/entities/ResourceDocumentationGenerator.java
@@ -44,12 +44,4 @@ public class ResourceDocumentationGenerator extends EntityDocumentationGenerator
 		return table;
 	}
 	
-	public void createUsageKnowledge() throws Exception {
-		ResourceType rt = (ResourceType) type;
-		UsageKnowledge fk = UsageKnowledge.getFacetKnowledge();
-		fk.addAll(rt.getFacets());
-		UsageKnowledge rk = UsageKnowledge.getResourceKnowledge();
-		rk.addAll(rt.getResources()); 
-	}
-
 }