เอกจิตต์ ขวัญษา, and สติมั่น อุทัย. “The Threefold Training and Self-development”. Journal of Educational Review Faculty of Education in MCU 3, no. 2 (September 5, 2018): 1701–179. accessed September 1, 2026. https://so02.tci-thaijo.org/index.php/EDMCU/article/view/144230.