Hi gant,

I think the following should do it. 
/ISBN \d+[ -]+\d+[ -]+\d+[ -]\d/;

[download]

Hope this helps

thinker
update I have realised that this is not a regex type question. I realise now that ISBN has it's own validating rules. Sorry. :-)

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

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