Kang-onta, Natwara, and Narissara Suaklay. 2026. “Guidelines for Developing 21st Century Management Skills for School Administrators Under the Chiang Rai Primary Educational Service Area Office 1”. Academic MCU Buriram Journal 11 (2):273-84. https://so06.tci-thaijo.org/index.php/ambj/article/view/292582.