The Chan (Zen) monk Yongsun Xu (用孙序) of the Qing Dynasty is known for his commentaries on classical Chan texts, particularly his detailed exegesis of the Transmission of the Lamp (Jingde Chuan Deng Lu). He also authored the "Collected Teachings of the Two Masters of the Mountain" (山中二老语录), a significant work in the Southern Chan lineage.