how can delete book from ibooks completely? I have a problem with iBooks that I download a book from iBook but I cant remove a totally the source of this book.

how can solve this problem?

I edit this text because I didn't write about the device to delete from.

my device is MacBook Pro and I like to delete source of a file in types .epub from my iBooks but I cant do this and after removing the file from iBooks the book it's there and I just can hide it!
To delete a book from iBooks on iOS


Click the select button in the top right of your screen
Select the book you want to delete
Click the delete button in the top left of your screen 
Click delete everywhere to delete he book from all your devices (if applicable) or press remove download to remove it from just your current device.