Pusit Rujjanavet. (1986) The phonology of Ugong in Uthaithani province. Mahidol University,:ม.ป.ท.Pusit Rujjanavet. 1986. The phonology of Ugong in Uthaithani province. ม.ป.ท.:Mahidol University,;Pusit Rujjanavet. The phonology of Ugong in Uthaithani province. ม.ป.ท.:Mahidol University, 1986. Print.