The Ex Erotica section on The Digital Exlibris Museum Project (Frederikshavn Art Museum & Exlibris Collection) is nothing short of amazing.
An exlibris (bookplate) is a mark of ownership which the owner of a book sticks into the inside of the cover. It is made by an artist who is commissioned by the owner to create according to his wishes and ideas a small graphic that bears the owner’s name and the word Exlibris.
(…) They have existed since Gutenberg’s invention of movable letters around 1500.
(…) The exlibris should clearly state the owner’s name and can allude to the personality by using motifs that illustrate the profession, hobbies or place of living. (art-exlibris.net/whatisexlibris)
Click through if you want to see larger sizes of these.