In Kao Gong Ji: A Translation and Commentary, Guan Zengjian and Konrad Herrmann offer an English translation and commentary of the first technological encyclopaedia in China. This work came into being around the 5th century C.E. and contains descriptions of thirty technologies used at the time. Most prominent are bronze casting, the manufacture of carriages and weapons, a metrological standard, the making of musical instruments, and the planning of cities. The technologies, including the manufacturing process and quality assurance, are based on standardization and modularization. In several commentaries, the editors show to which degree the descriptions of Kao Gong Ji correspond to archaeological findings.