 In the centuries that followed, several shorter books tried to summarize or systematize its contents of the book "Yellow Emperor's Inner Canon".The "Canon of Problems" (probably second century CE) tried to reconcile divergent doctrines from the "Inner Canon" and developed a complete medical system centered on needling therapy.The "AB Canon of Acupuncture and Moxibustion" ("Zhenjiu jiayi jing" , compiled by Huangfu Mi sometime between 256 and 282 CE) assembled a consistent body of doctrines concerning acupuncture; whereas the "Canon of the Pulse" ("Maijing" ; ca.