diff --git a/SemanticData/UANodeSetValidation/AddressSpaceContext.cs b/SemanticData/UANodeSetValidation/AddressSpaceContext.cs
index 2d123fa5..60226726 100644
--- a/SemanticData/UANodeSetValidation/AddressSpaceContext.cs
+++ b/SemanticData/UANodeSetValidation/AddressSpaceContext.cs
@@ -216,6 +216,7 @@ IEnumerable<UAReferenceContext> IAddressSpaceBuildContext.GetReferences2Me(IUANo
     /// </summary>
     /// <param name="node">The root node of the requested children.</param>
     /// <returns>Return an instance of <see cref="IEnumerable{IUANodeBase}" /> capturing all children of the selected node.</returns>
+    //TODO NetworkIdentifier is missing in generated Model Design for DI model #51
     public IEnumerable<IUANodeBase> GetChildren(IUANodeBase node)
     {
       return m_References.Values.Where<UAReferenceContext>(x => Object.ReferenceEquals(x.SourceNode, node)).
diff --git a/SemanticData/UANodeSetValidation/UANodeContext.cs b/SemanticData/UANodeSetValidation/UANodeContext.cs
index a381ff33..244a3fa8 100644
--- a/SemanticData/UANodeSetValidation/UANodeContext.cs
+++ b/SemanticData/UANodeSetValidation/UANodeContext.cs
@@ -155,6 +155,7 @@ void IUANodeBase.CalculateNodeReferences(INodeFactory nodeFactory, IValidator va
         switch (_rfx.ReferenceKind)
         {
           case ReferenceKindEnum.Custom:
+            //TODO NetworkIdentifier is missing in generated Model Design for DI model #51
             XmlQualifiedName _ReferenceType = _rfx.GetReferenceTypeName();
             if (_ReferenceType == XmlQualifiedName.Empty)
             {
@@ -189,6 +190,8 @@ void IUANodeBase.CalculateNodeReferences(INodeFactory nodeFactory, IValidator va
           case ReferenceKindEnum.HasTypeDefinition: //TODO Recognize problems with P3.7.13 HasTypeDefinition ReferenceType #39
             IsProperty = _rfx.TargetNode.IsPropertyVariableType;
             break;
+          case ReferenceKindEnum.HierarchicalReferences:
+            throw new ArgumentOutOfRangeException($"the {nameof(ReferenceKindEnum.HierarchicalReferences)} is not handled");
         }
       }
       Dictionary<string, IUANodeBase> _derivedChildren = m_BaseTypeNode == null ? new Dictionary<string, IUANodeBase>() : m_BaseTypeNode.GetDerivedInstances();
@@ -272,6 +275,7 @@ public XmlQualifiedName ExportBrowseNameBaseType(Action<NodeId> traceEvent)
     /// </summary>
     /// <returns>Dictionary&lt;System.String, IUANodeBase&gt;.</returns>
     /// <exception cref="ArgumentOutOfRangeException">Circular loop in inheritance chain</exception>
+    //TODO NetworkIdentifier is missing in generated Model Design for DI model #51
     public Dictionary<string, IUANodeBase> GetDerivedInstances()
     {
       if (m_InGetDerivedInstances)
diff --git a/SemanticData/UANodeSetValidation/UAReferenceContext.cs b/SemanticData/UANodeSetValidation/UAReferenceContext.cs
index 27586374..3f1bdf38 100644
--- a/SemanticData/UANodeSetValidation/UAReferenceContext.cs
+++ b/SemanticData/UANodeSetValidation/UAReferenceContext.cs
@@ -49,6 +49,7 @@ internal UAReferenceContext(Reference reference, IAddressSpaceBuildContext addre
     /// Gets the kind of the reference.
     /// </summary>
     /// <value>The kind of the reference.</value>
+    //TODO NetworkIdentifier is missing in generated Model Design for DI model #51
     internal ReferenceKindEnum ReferenceKind
     {
       get
@@ -86,6 +87,7 @@ internal ReferenceKindEnum ReferenceKind
     /// Gets a value indicating whether the reference has been derived form <see cref="ReferenceKindEnum.HasProperty"/> or <see cref="ReferenceKindEnum.HasComponent"/>.
     /// </summary>
     /// <value><c>true</c> if it is child reference; otherwise, <c>false</c>.</value>
+    //TODO NetworkIdentifier is missing in generated Model Design for DI model #51
     internal bool ChildConnector => (ReferenceKind == ReferenceKindEnum.HasProperty) || (ReferenceKind == ReferenceKindEnum.HasComponent);
 
     #endregion semantics