Zuiho Yamaguchi specialized in the history of Tibet. His studies included the manuscripts of Dunhuang, but also dealt with other subjects, such as the Tibetan calendar, on which he published a work in 1973 in Japanese. He also did a thorough investigation of facts surrounding emperor Langdarma, where he challenged the assertion that Langdarma was a persecutor of Buddhism and a supporter of Bon. (Source Accessed June 19, 2020)
