พานจันทร์ ท., ตันตินาครกูล อ., and บุญภักดิ์ ก. “Factors Affecting Self-Development of Teachers in Secondary Schools Under The Jurisdiction of The Secondary Educational Service Area Office 2”. Journal of Industrial Education, vol. 14, no. 3, Dec. 2015, pp. 561-8, https://ph01.tci-thaijo.org/index.php/JIE/article/view/122829.