Jia Yi
In the 1st century AD, many of the first books about acupuncture were published and recognized acupuncturist experts began to emerge. The "Zhen Jiu Jia Yi Jing", which was published in the mid-3rd century, became the oldest acupuncture book that is still in existence in the modern era. Other books like the "Yu Kuei Chen Ching", written by the Director of Medical Services for China, were also influential during this period, but were not preserved. In the mid 7th century, Sun Simiao published acupuncture-related diagrams and charts that established standardized methods for finding acupuncture sites on people of different sizes and categorized acupuncture sites in a set of modules.