diff --git a/pom.xml b/pom.xml
index 44c87cdd..0938c714 100644
--- a/pom.xml
+++ b/pom.xml
@@ -331,6 +331,9 @@
 								<toclevels>4</toclevels>
 								<numbered>true</numbered>
 							</attributes>
+							<requires>
+								<require>asciidoctor-diagram</require>
+							</requires>
 						</configuration>
 
 					</plugin>
diff --git a/src/main/asciidoc/fundamentals.adoc b/src/main/asciidoc/fundamentals.adoc
index 49483b1e..e7b97deb 100644
--- a/src/main/asciidoc/fundamentals.adoc
+++ b/src/main/asciidoc/fundamentals.adoc
@@ -111,16 +111,19 @@ For more information on this, have a look at <<mediatypes>>.
 ====
 [plantuml, diagram-classes, format="svg"]
 ....
+hide fields
+hide methods
+
 class RepresentationModel
 class EntityModel
 class CollectionModel
 class PagedModel
 class SlicedModel
 
-EntityModel -|> RepresentationModel
-CollectionModel -|> RepresentationModel
-PagedModel -|> CollectionModel
-SlicedModel -|> CollectionModel
+EntityModel -up-|> RepresentationModel
+CollectionModel -up-|> RepresentationModel
+PagedModel -up-|> CollectionModel
+SlicedModel -up-|> CollectionModel
 ....
 ====