บุญวัฒนะกุล ชนกนารถ. “A Synthesis of Graduate Students Research in Non-formal and Informal Education, School of Educational Studies, Sukhothai Thammathirat Open University”. STOU Education Journal 10, no. 2 (May 13, 2018): 152–163. accessed October 13, 2026. https://so05.tci-thaijo.org/index.php/edjour_stou/article/view/128795.