Xu Zizhi Tongjian Changbian
The Xu Zizhi Tongjian Changbian (續資治通鑑長編; "Extended Continuation to Zizhi Tongjian") was an important book chronicling Chinese history of Northern Song Dynasty between 976–1126. Written by Li Tao (1114–1183), a secretary in the Veritable Records Institute (實錄院) in the Southern Song Dynasty, the book took 40 years to complete and was finally published in 1183. As the sequel to Sima Guang's landmark work Zizhi Tongjian (資治通鑑; "Comprehensive Mirror to Aid in Government"), it follows the same format, but is not as concise and refined. Of the original 980 volumes only 520 are extant.