Karen said concerning ISBNs:

>... it's only be in use for the last 50 years of book 
>publishing, only covers books ...

About 1/3rd of the DVDs we do now have ISBNs, as well as often other
standard numbers.  While it is true books published earlier lack
ISBNs, so do some modern books.

There is also the question of erroneous ISBNs, and a single
manifestation with more than one ISBN, e.g., simultaneous publication,
different bindings.

There are also several other standard numbers for books and
bibliographic records to be considered.

   __       __   J. McRee (Mac) Elrod ([log in to unmask])
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