Due to scanty and imprecise documentary evidence, the late career of Muhammad Yūsuf and the date of his death remain uncertain. According to Joseph Fletcher's research, Muhammad Yūsuf had worked among Hui and Salar people in present-day Gansu and Qinghai provinces in the mid-17th century, then returned to Altishahr and died there in 1653, poisoned by his rivals. On the other hand, the dean of Hui studies in China, Ma Tong, thought that Muhammad Yūsuf died in 1622, and all preaching in Qinghai and Gansu was done by his son Afāq Khoja. (Lipman, Jonathan Neaman (1998). Familiar strangers: a history of Muslims in Northwest China. Hong Kong University Press. p. 59. ISBN962-209-468-6. Archived from the original on 2017-01-09. Retrieved 2016-09-21. Lipman's source is: Joseph Fletcher, "The Naqshbandiya in Northwest China", in Beatrcie Manz, ed. (1995). Studies on Chinese and Islamic Inner Asia. London: Variorum.)
Due to scanty and imprecise documentary evidence, the late career of Muhammad Yūsuf and the date of his death remain uncertain. According to Joseph Fletcher's research, Muhammad Yūsuf had worked among Hui and Salar people in present-day Gansu and Qinghai provinces in the mid-17th century, then returned to Altishahr and died there in 1653, poisoned by his rivals. On the other hand, the dean of Hui studies in China, Ma Tong, thought that Muhammad Yūsuf died in 1622, and all preaching in Qinghai and Gansu was done by his son Afāq Khoja. (Lipman, Jonathan Neaman (1998). Familiar strangers: a history of Muslims in Northwest China. Hong Kong University Press. p. 59. ISBN962-209-468-6. Archived from the original on 2017-01-09. Retrieved 2016-09-21. Lipman's source is: Joseph Fletcher, "The Naqshbandiya in Northwest China", in Beatrcie Manz, ed. (1995). Studies on Chinese and Islamic Inner Asia. London: Variorum.)
