Spohr Publishers publish books for Muslims and for those who are interested in Islam, and people say that their books are the most beautiful in this field: from the perspective of texts, the editing, and their shape, as well as from the physical attributes of the books, i. e. the way you may handle it, its off-flat character and the solidity of its shape and its bonding, either glued or thread-stiched.
They are a German publishing outfit, and for around twenty years we have been producing books in an advanced way by following classic rules of this art in typesetting, page layout, paper, binding, etc. So if there is enough space you will find the writing on the spines horizontally adjusted so that there is no need to tilt your head by 90 degrees when trying to read the text on the spine of the book.