DJVU PDF Migliazza, B. 2003, "So stories: a preliminary analysis of texts in a Mon-Khmer language", in The Mon-Khmer Studies Journal, vol. 33, pp. 67-158. cite.

Migliazza, B 1998, "A grammar of So ---A Mon-Khmer language of Northeast Thailand", PhD thesis, Mahidol University. cite.

DJVU PDF Migliazza, B.L. 1992, "Lexicostatistic analysis of some Katuic languages", in The Third International Symposium on Language and Linguistics, Bangkok, Thailand, pp. 1320-1325. Chulalongkorn University. cite.