How to clean ISBN book title

[jpottsx1]

I have been trying hard but cannot seem to figure out how to a book title that contains the ISBN, and using a REGEX, copy just the ISBN either back to the title field or how to copy the ISBN to the Identifier field.

I have tried using "ISBN\x20(?=.{13}$)\d{1,5}([- ])\d{1,7}\1\d{1,6}\1(\d|X)$" but I still get all the extra garbage in the filename.

Any insights on way to do this?

Jeff