Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Object Groupings and Systems (hierarchy name)
4. object groupings
5. [object groupings by general context]

Anotations

Scope note:

Groups of all copies printed at the same time. A single impression in publishing includes all of the copies of a book produced during one printing, or print-run, or an additional press-run made without revision of text.