"In this background, it would be an unremitting task both in volume and repetition to give all anecdotes, facts and figures of enslavement and concubinage of captive women in the central and provincial kingdoms and independent Muslim states found mentioned in the chronicles. This would only lead to repetition resulting in the book becoming bulky."
January 1, 1970
https://en.wikiquote.org/wiki/History_of_concubinage_in_the_Muslim_world