As you know I post all the hardback editions (here). But I get a lot of questions "how do I know I am buying that edition?" Well. There is this thing called ISBN in every book (some author edition might not have it. I have 1 or 2 like that but they are all Portuguese).
The ISBN is the little 13 number code on top of the bar code.
But every edition has a different code. Like a fingerprint. On my posts I always say the number of the exact edition. That way you can put that number on Google, book depository, Amazon, etc, etc and you will find the exact edition of the book.
That's normally how that happens. I am afraid some paperbacks or edition changes might have same ISBN but that's something I couldn't confirm yet because I don't have the books.
How to check it on some websites:
