A set of Nodes.
Node Set is a kind of Concept System. Here are 2 examples:
The version of the object assigned by the owning agency.
Version designator (defaults to “1.0”)
The organization or legal entity which owns and maintains the object.
A human-readable internal note intended for the developers/maintainers of GSIM.
The effective date on which the object is published.
The effective date on which the object is withdrawn from publication.