Analysis of information sources in references of the Wikipedia article "Kachin Hills" in English language version.
In 1910 the British, then established in Burma, induced the tusi of Pianma (Hpimau) to defect from the central Chinese government, and they then occupied his territory in northwestern Yunnan. Britain also forced China to give up a tract of territory in what is now the Kachin state of Myanmar (1926–27), as well as the territory in the Wa states (1940).
Agreement on the Question of the Boundary signed on January 28, 1960...(b) the villages of Hpimaw, Gawlum, and Kangfang would be Chinese;...(d) the Panhung-Panlao tribal area would be exchanged (for Namwan); and (e) with the exception of d, the 1941 boundary in the Wa states would be accepted...
Agreement on the Question of the Boundary signed on January 28, 1960...(b) the villages of Hpimaw, Gawlum, and Kangfang would be Chinese;...(d) the Panhung-Panlao tribal area would be exchanged (for Namwan); and (e) with the exception of d, the 1941 boundary in the Wa states would be accepted...