advance sheets
1. A copy of a book, in sheets or gatherings, for
preliminary notices, simultaneous publication in
two or more places, or for early cataloging.
Advance sheets for review or early cataloging are
usually in unbound gatherings. 2. Generally,
sheets of a publication e.g., some serial
publications or other documents, printed
separately for use before they are issued
collectively. In a stricter sense these are more
appropriately called "preprints." (69 , 140 )