ISBN:

This interface does not check that you have typed in a legal ISBN (which should be 9 digits followed by a digit or an `X'), except that any characters which are not digits or `X' (ISBNs are typically quoted with spaces or hyphens for punctuation) are stripped before the query page is made up. It is up to you to get the ISBN right.

Note that ISBNs do not identify what most people call a `book', but vary with format and edition. The library does the sensible thing if you quote an ISBN when you order.