Metadata from calibre converted epub

[wannabee]

Just wondering how to handle this correctly.

I've learned how to make ePubs thinking Calibre will make the Mobi for me. And . . . so far it has. They look good and the TOC shows up and works when you select the TOC button on MobiPocketReader for PC and Kindle app for iPad.

But my question is: What about the ISBN Metadata from the epub. It's unique ID in the content.opf and toc.ncx is it's ISBN. The Mobi should have it's own ISBN. Do I have to edit the Mobi to add the Mobi's ISBN?

I haven't uploaded anything to Amazon or iBookstore yet. I think there is a field to add ISBN Author etc. as it's being uploaded and they'll take care of it in their store but we plan to make it available from our store as well. It's not a book store, lotions and potions just have barcodes printed on the label not on the inside of an already sealed container.

All of the ISBNs are noted on the title pages as such:

Paperback USA ISBN 0958613710
ePub ISBN 978-1-936609-02-4
Kindle ISBN 978-1-936609-03-1
PDF ISBN 978-1-936609-04-8

Is that enough? How will the libraries handle the books? Will they somehow take care of the ISBN metadata through their systems? Your insight would be appreciated.