The References ReferenceType is an abstract ReferenceType; only subtypes of it can be used.
There is no semantic associated with this ReferenceType. This is the base type of all ReferenceTypes. All ReferenceTypes shall be a subtype of this base ReferenceType – either direct or indirect. The main purpose of this ReferenceType is allowing simple filter and queries in the corresponding Services of OPC 10000-5.
There are no constraints defined for this abstract ReferenceType.