On Tue, 14 May 2013 15:33:07 -0700, Karen Coyle <[log in to unmask]> wrote:

> From the Bowker site:
>"Once a barcode is made, it cannot be revised. If you want to change the
>price of an item, you must purchase a new bar code. However, you can use
>the same ISBN as long as the product and price have not changed."
>(I wonder about the O'Reilly books that first come out in Beta form --
>whether the final form gets a new ISBN. ?)
>Of course, rules are just rules, so some duplication of barcodes does
>happen, especially if (usually small) publishers don't want to pay for a
>new one.

The Bowker information at least helps me understand why some reprints carry 
different barcodes, without any difference that seems to constitute a 
revision or new edition under the rules we're accustomed to.  I see little 
evidence that many publishers follow this practice, though.

Many publishers in the past, and still some these days, who use the ISBN as 
their internal stock control ID, seem to believe that when a new issue comes 
into stock they can continue to use the same ISBN.  They have no interest in 
the wider field of bibliographic control beyond the commercial level.

Moroeover, practice in lultipart items differs.  Some print publishers give 
a separate ISBN to each part or volume, and another to the complete set of 
volumes or parts as a whole.  ISBN is not a watertight identifier for all 

Hal Cain
Melbourne, Australia
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