Of the five ISBN modules that I could find on CPAN, the most relevant for your "CGI-Perl problem" is probably CGI::Untaint::isbn. It will untaint and validate an ISBN passed as a CGI parameter.

Other (less) relevant modules are: Test::ISBN and Business::ISBN.

In reply to Re: CGI -Perl problem by Mr. Muskrat
in thread Validating ISBN numbers? by gant

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