The user may define subclasses of this class.
An instance of Source identifies the administrative aspects of where the data comes from, where it is going, and possible restrictions on the data. The producer, distributor and receiver (which can all be provided) are typically organizations or individuals. The database provides a DBMS identification. The project contains a general description of the project associated with the source of the data. The releasability attribute holds any designation or comment associated with the provision of the data to users. Legal and security information can be provided, as well as general remarks.