Sou
The Sou (Souk) are a group of about 1,000 (1962) in Attopeu Province in southern Laos, who by now may be totally assimilated into Laotian society.
Bibliography
Hoffet, J. (1933). "Les Moïs de la chaîne annamitique." Tene, Air, Mer: La Géographie 59:1-43.