Hows it goin, i'm goin a project where i have to use validation rules..which is fair enough but i am havin problems with validating aN ISBN. This has to be:
The ten-digit number is divided into four parts of variable length, which must be separated clearly by hyphens or spaces:

ISBN 0 571 08989 5

or

ISBN 90-70002-34-5

Note: Experience suggests that hyphens are preferable to spaces.

The number of digits in the first three parts of the ISBN (group identifier, publisher prefix, title identifier) varies. The number of digits in the group number and in the publisher prefix is determined by the quantity of titles planned to be produced by the publisher or publisher group. Publishers or publisher groups with large title outputs are represented by fewer digits.

I would be grateful for any help.
cheers
gant

update (broquaint): title change (was CGI -Perl problem) and added formatting

In reply to Validating ISBN numbers? by gant

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