郑玄
The first reference to a book being used in learning mathematics in China is dated to the second century CE (Hou Hanshu: 24, 862; 35,1207). We are told that Ma Xu (a youth ca 110) and Zheng Xuan (127-200) both studied the "Nine Chapters on Mathematical procedures". C.Cullen claims that mathematics, in a manner akin to medicine, was taught orally. The stylistics of the "Suàn shù shū" from Zhangjiashan suggest that the text was assembled from various sources and then underwent codification.