Hi,
I've looked on the wikipedia booksource page and in the archives for the list, and I don't see any conclusions about this topic, so I'll throw it out there. Has there been discussion about using LCCNs, OCLC numbers, or some other standard number for books that were published before ISBNs? It would be nice to be able to provide a link to the unique work in citations where ISBN isn't available, and OCLC number is one way to do so, which works with OCLC and with lots of libraries' OPACs.
I'm guessing this would work something like: OCLCNUM 45951519
For which one link option would be: http://www.worldcat.org/oclc/45951519
Thanks, Matt