خزائن خزائن كتب المساجد والأربطة البغدادية في كتاب تلخيص مجمع الآداب في معجم الألقاب لابن الفوطي(ت723هـ/1323م)
The Abbasid period is one of the most fertile Islamic ages attention to the bookcases have been prominent of each of the caliphs, ministers and dignitaries acquisition of books and stop in the coffers of public books, so that the largest number of students of science to see them. Baghdad's portfolio of scientific status in the late Abbasid times, which was characterized by weakness and division