1930年，中瑞西北考察团的大卫·哈默尔（David Hummel）、德国人包肯坎普（Manfred Bökekamp）和姓张的中国学生抵达迭山北坡，沿着秦仁昌的路线到扎尕那、石门、阿角沟进行人类学、植物学考察，他们在扎尕那村收集了许多民俗物品，至今仍在瑞典展览。
David Hummel among the Tebbu Tibetans
The eastern flank of the Tibetan cultural region consisted, before the communist takeover in China, of a patchwork of small Tibetan kingdoms and monastic states. Furthest to the northeast lay Choni, a kingdom with a famous monastery containing one of Tibetan civilization's large printing works. The southern part of the realm was inhabited by Tebbu (Tewo) Tibetans who, during troubled times, served in the army as the king's foot-soldiers. They had to fight against other Tibetans, against Chinese Muslims, Hui, and against bandit armies.
In 1930 David Hummel (1893-1985) braved hard...