Wongpichet, Seree, and Cumnueng Watyotha. “The Suitability of The Utilization of Small Second-hand Agricultural Tractor : Case Study in Khon Kaen Province”. Engineering and Applied Science Research 31, no. 2 (March 5, 2013): 123–132. accessed September 27, 2026. https://ph01.tci-thaijo.org/index.php/easr/article/view/6707.