NewsItemId

An identifier for the NewsItem. The combination of a NewsItemId and a DateId must be unique among NewsItems that emanate from the same provider. Within these constraints, the NewsItemId can take any form the provider wishes. It may take the form of a name for the NewsItem that will be meaningful to humans, but this is not a requirement. The provider may optionally relate the values of a NewsItemId to a controlled vocabulary, which is invoked by the Vocabulary attribute. The value of the Vocabulary attribute may be an http URL, a NewsML URN, or the # character followed by the value of the Duid attribute of a TopicSet in the current document.  The Scheme attribute, if present, serves to distinguish which of possibly multiple naming schemes in the controlled vocabulary is the one that governs the NewsItemId.