Wikipedia page about this book: https://en.wikipedia.org/wiki/Zhoubi_Suanjing

Release date is 2004-05-01

"周髀算經" by Unknown is an ancient Chinese astronomical and mathematical work that received its current form during the Eastern Han dynasty (25–220 AD). This anonymous collection presents 246 problems involving celestial calculations and geometric relationships, claiming origins with the Duke of Zhou's court. The work explores Chinese cosmology's concept of a round heaven over a square earth, analyzes solar movements through gnomon shadows, and presents an early form of the Pythagorean theorem known as the gougu theorem—sparking debate about whether Chinese mathematicians discovered this principle independently. (This is an automatically generated summary.)

Original publication data not identified