Collection:

A group of graphic items, including associated materials, either acquired by the repository as an existing collection or assembled by the repository into a unit for cataloging purposes.  The items, whether individually published or not, do not as a collection constitute a multipart publication.  However they were formed, a collection is cataloged as a unit in order to reflect one or more of the following characteristics:

(1)  the items are the product or collection of one or more persons or family group;

(2)  the items are the product or collection of a corporate body;

(3)  the items represent the creative effort of one person, group, or corporate body;

(4)  the items were brought together by a collector, and it is necessary or desirable to maintain them as a unit even if there are disparate subjects or different formats;

(5)  the items were designated a "collection" at the time of accessioning, with the requirement that the items not be disseminated;

(6)  the items have inherent unity by virtue of a single topic or several thematically related topics;

(7)  the items have inherent unity by virtue of their medium or format.

Subunits within collections may be formed according to the same characteristics.