Nisachon Channukool. (1998) Factors related to the prevalence of Enterobius vermicularis infection in Nhong-Sum-Rong school children, Udornthani. Mahidol University,:ม.ป.ท.Nisachon Channukool. 1998. Factors related to the prevalence of Enterobius vermicularis infection in Nhong-Sum-Rong school children, Udornthani. ม.ป.ท.:Mahidol University,;Nisachon Channukool. Factors related to the prevalence of Enterobius vermicularis infection in Nhong-Sum-Rong school children, Udornthani. ม.ป.ท.:Mahidol University, 1998. Print.