Buntha, C., A. Akkasang, and S. Chardchawarn. “Investigating the Corruption Method in Procurement Process Within the Sub-District Administrative Organizations in Maha Sarakham Province”. Chophayom Journal, vol. 28, no. 3, Dec. 2017, pp. 36-44, https://so01.tci-thaijo.org/index.php/ejChophayom/article/view/107021.