Pongsiri Prathnadi. 1991. Inicidence of cholelithiasis in the northern part of Thailand. Chiang Mai:Chiang Mai University;
Pongsiri Prathnadi. (1991) Inicidence of cholelithiasis in the northern part of Thailand. Chiang Mai University:Chiang Mai.
Pongsiri Prathnadi. Inicidence of cholelithiasis in the northern part of Thailand. Chiang Mai:Chiang Mai University, 1991. Print.
Pongsiri Prathnadi. (1991) Inicidence of cholelithiasis in the northern part of Thailand. Chiang Mai University:Chiang Mai.