Can I get non-iBooks Store ePub files into my iCloud iBooks library? I buy quite a few ePub e-books from sources other than the iBooks Store.

I used to use iTunes to sync these to my iPad and iPhone. However, I’m trying to set up my iPad and iPhone to purely sync through iCloud, as syncing with both iCloud and iTunes gets a bit confusing.

Can I get non-iBooks Store ePub files into my iCloud iBooks library, so that they live there? (i.e. so that if I do a restore on my iPad or iPhone, I’ll be able to download them from iCloud again.) If so, how?
You can email yourself the files, then from Mail, open the files in iBooks.