to the bibliographical system devised by Liu Xiang and Liu Xin with minor exceptions. The introductory paragraph of the treatise, most likely taken verbatim from Qilue, is quite informative:

"Many books were in great disarray in the time of Chengdi, upon which Chen Nong (??) was ordered to collect all the books in the world, and high officials to collate books in the Imperial Library; Luminous Grand Master, Liu Xiang, was put in charge of works by the Confucians, the philosophers, and the shi and fu poets;