Interesting Things with JC #461: "Where Traditional Kampo Medicines of Japan Came From" - Researchers from Japan and China, led by Professor Toshihiko Matsuo of Okayama University's Graduate School of Interdisciplinary Science and Engineering in Health Systems, conducted a thorough review of available Chinese, Japanese, and English literature in order to shed light on a long-standing mystery.

Ref - https://www.researchgate.net/publication/364420631_Traditional_Chinese_Medicines_and_Prescriptions_Brought_from_China_to_Japan_by_a_Monk_Jianzhen_Japanese_Ganjin_A_Historical_Review

Liu, Shihui & Matsuo, Toshihiko & Matsuo, Chie & Abe, Takumi. (2022). Traditional Chinese Medicines and Prescriptions Brought from China to Japan by a Monk (Jianzhen, Japanese: Ganjin): A Historical Review. Compounds. 2. 267-284. 10.3390/compounds2040022.