Verify an Edition

Type the thirteen-digit ISBN printed on the copyright page of your copy. The ledger will tell you which volume it is, when it was printed, how many were made and whether it is still in circulation.

Check the ledger

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Notes on the ledger

Halbrook ISBNs all begin 978-1-90473-1. The two digits that follow are the volume number; the final digit is the standard check digit and is calculated, not chosen. If you have a Halbrook book in front of you, the number on the copyright page is the number the ledger expects.

Records are held encrypted and the ISBN you type is the key that opens them. This is not a security measure so much as a filing decision: it means a record cannot be read out of this page by somebody who does not have the book. It was done this way in January 2005 and nobody has since been willing to undo it.

Nothing you type is sent anywhere. The check runs in your browser. The office would not know what to do with the information if it received it.