- 九章律 jiǔzhānglǜ Nine Chapters of Lawlegal code from the early Han Dynasty compiled by Xiao He
- 九章算术 jiǔzhāngsuànshù The Nine Chapters on the Mathematical ArtThe Nine Chapters on the Mathematical Art; an ancient Chinese mathematics book compiled during the Western Han dynasty based on older texts, consisting of 246 problems categorized into nine chapters.