Location, where the external source (classification, document or library) can be accessed by electronic means. The electronic location is provided as an URI, and would normally be given as an URL location string.
The Identification provides a unique identifier of the referenced item within the external source (classification, document or library). It may be provided as * a key, e.g. a classification notation, like NF2.3 * a handle * a uuid or guid
It may be human readable (such as a key) or not (such as a handle or uuid) depending on the context of its usage (which has to be determined by local agreement).
Optional name to further specify the reference. It can provide a human readable identifier (which does not necessarily need to have a counterpart in the internal structure of the document).
|ExternalReferenceForResources||SET [0:?] OF IfcExternalReferenceRelationship FOR RelatingReference||
Reference to all associations between this external reference and objects within the IfcResourceObjectSelect that are tagged by the external reference.
ENTITY IfcExternallyDefinedTextFont SUBTYPE OF (IfcExternalReference); END_ENTITY;