DJVU PDF Phong, N.P. 1996, "Negation in Vietnamese and in some of the Viet Muong languages", in The Fourth International Symposium on Language and Linguistics, Thailand, pp. 563-568. Institute of Language and Culture for Rural Development, Mahidol University. cite.

DJVU PDF Nagarajan, S. 1992, "A note on negation in Tamil", in The Third International Symposium on Language and Linguistics, Bangkok, Thailand, pp. 216-231. Chulalongkorn University. cite.

DJVU PDF Lagsanaging, D. 1992, "Pragmatics of negation in Thai", in The Third International Symposium on Language and Linguistics, Bangkok, Thailand, pp. 1427-1439. Chulalongkorn University. cite.