Different editions, same ISBN?

[Barak]

I am new librarian.

I have the following edition, which is 394 pages long, published by Transworld Publishers.

Curiously, it has the same ISBN as this one, which was published a year later and contains 320 pages only.

How is that possible, and how do I add my edition in such a case?!

[Kim]

It needs to be added as an alternate edition.

[Barak]

Gotcha! Thanks.

[Barak]

Hmmm... I added the aforementioned edition almost 3 hours ago. I was told it was successful and that it takes 10 minutes until it will be searchable.

However, the number of editions is still the same as it was before for this book and I cannot find my addition anywhere... (did it go to an alternate reality?)

[Jessica]

I've combined the editions.

[Barak]

Thanks! thought it might be something like that, but could not find it in order to try it.