evidence: In January 1965, however, Cambodia in a note to South Vietnam advanced claims to several areas of South Vietnam that she had claimed historically but that had been ceded to Vietnam through various French decrees. These in- cluded: (1) part of the Cambodian province of Stung Treng, which was incor- porated into Darlac Province of Armem in 1899, (2) four districts (cantons) [...] The first definition of the boundary was contained in the 1893 treaty between France and the Kingdom of Siam, by which France forced expanding Siam to give up all teriltbry east of the Mekong River. As a result of this treaty, the former Canbodian province of Stung Treng (part of which now com- prises the Cambodian provinces of Stung Treng and Ratanakiri) became part of [...] Cambodian boundary at the Col de Fresh Chambot. Thus, the Province of Chem- passak and the western portion of Sithandone Province, in the extreme south- western pert of Laos, like Sayaboury Province, are separated faKm the remain- der of Laos by the Mekong River, and in these areas the boundary between