AllowedValues

						The AllowedValues attribute, if present, is a pointer to a controlled vocabulary that delimits the set of allowed values for the property. This may be an http URL, or a NewsML URN, or a fragment identifier consisting of a # charactger followed by the Duid of an element in the current document. The pointer must reference either a Resource element that designates an external controlled vocabulary, or a TopicSet element, that is itself the controlled vocabulary.