Delete selected books from iCloud

Has anyone figured out yet how to delete books from iCloud. I have books that I bought years ago and don't want to keep any longer. They're cluttering up my iCloud storage and even though I can "hide" them on my iPad they're still there lurking in "hidden lists".

PLEASE ADVISE HOW TO DELETE UNWANTED PURCHASED BOOKS. I PAID FOR THESE BOOKS AND IF I WANT TO TRASH THEM, I SHOULD HAVE THE ABILITY AND CONTROL TO DO SO. IF I DECIDE I WANT THE BOOK IN THE FUTURE THEN I'LL HAVE TO PAY FOR IT AGAIN.