Jumpasri, P. “Factors Affecting Access to Higher Positions of Supporting Staff Rajabhat Maha Sarakham University”. Journal of Research and Development Institute Rajabhat Maha Sarakham University, vol. 5, no. 1, Dec. 2018, pp. 101-14, https://so03.tci-thaijo.org/index.php/rdirmu/article/view/210508.