ePub is the standard on which Amazon’s MOBI Kindle files are based. ePub is supposed to the same for every retailor. That’s not my experience. There are minor quirks depending on where you submit your ePub file.
The format is similar to that required for Kindle MOBI . The limitations and requirements are similar. All of my ePub files pass the official ePub validation. However a file can pass the standard validation and still fail to be accepted by various eBook retailors. I however guarantee that I will work with you until the file is accepted. However, the most common reason your file will be rejected, has nothing to do with formatting, it’s because you mention the “A”-word!
Don’t Mention Amazon!
You will need to make some editorial changes. In particular you should remove any mention of, and links to, books sold on Amazon. If you are publishing the ePub version widely I strongly suggest that you link instead to your author website where your reader can chose where to buy other books in the series.
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