The HasEncoding ReferenceType is a concrete ReferenceType and can be used directly. It is a subtype of NonHierarchicalReferences.
The semantic of this ReferenceType is to reference DataTypeEncodings of a subtype of the Structure DataType.
The SourceNode of References of this type shall be a subtype of the Structure DataType.
The TargetNode of this ReferenceType shall be an Object of the ObjectType DataTypeEncodingType or one of its subtypes (see 5.8.4).