The Nine Chapters on the Mathematical Art
It was specified in Tang dynasty laws on examination that "Sunzi Suanjing" and the "Computational Canon of the Five Administrative Sections" together required one year of study; "The Nine Chapters on the Mathematical Art" plus "Haidao Suanjing" three years; "Jigu Suanjing" three years; "Zhui Shu" four years; and "Zhang Qiujian" and "Xia Houyang" one year each.