It is no longer possible (as far as I can tell) to email an epub document to your iPad (or iPhone). I have, however, found and tested two ways to make a transfer to the new iOS app, Books. 1) Using iTunes: Attach your iPad (or iPhone) to iTunes on your computer. Drag (transfer) the unzipped epub file directly to the iTunes-folder Books on your device. 2) You can download the zip-file bundle directly to your iPad (or iPhone) from this site. It will appear in the Files app. Click the downloaded zip file, then click on the epub file. It will appear and be saved in the Books app.