Sharing books
You may share any of the books via sharing option. Such a function is available in “Information about the book” section (in the reading window, or in “⋮” menu next to the book) as well as in the “⋮” menu of the book.
Click on the share icon and choose the method, most comfortable for you, via which you desire to share a book. In order to do this, you may use any of the installed messengers, e-mail clients, etc.