The four massive literary collections compiled during the Northern Song dynasty, comprising the [[太平广记|太平廣記|tai4 ping2 guang3 ji4]], [[太平御览|太平御覽|tai4 ping2 yu4 lan3]], [[册府元龟|冊府元龜|ce4 fu3 yuan2 gui1]], and [[文苑英华|文苑英華|wen2 yuan4 ying1 hua2]]