Name that legacy classification system

All call numbers begin with A. As of the late 80s/early 90s, only used at the U.S. Census Bureau Library (which was phasing it out in favor of LC) and a library that might have been in Chicago.

The A-system? Sorry, couldn't resist :-)

Are you trying to figure it out, or is this a pop quiz? ;)

There's a very good chance it's SuDoc:
https://www.fdlp.gov/about-fdlp/22-services/929-sudoc-classification-scheme

Hi all,

Thanks for your responses. To answer melannen: I am trying to figure it out.

I looked at SuDoc, and that was very promising. However it cannot be what I am looking for, because it seems to still be in use in a number of places. The one I am thinking of had only two libraries using it in the early 1990s.

The search continues.

>5 alanhecht: - can you give us the background? What are you basing the "only two libraries using it" on? (we might be able to backtrace if we have some more info).

Ah, I think I've got it: Glidden and Marchus classification?

https://babel.hathitrust.org/cgi/pt?id=mdp.39015030784295&view=1up&seq=7...

ETA: Based on the snippet at https://books.google.com/books?newbks=1&newbks_redir=0&id=NYsaAAAAMAAJ&a...

>3 melannen: If it's a pop quiz, >7 JBD1: just won the golden ticket, it looks like. Well done!!