สิงห์ทองค., and นามวรรณธ. “The Development of Creative Leadership Program for Teachers in Schools under Secondary Educational Service Area Office 20”. Journal of Roi Et Rajabhat University, Vol. 12, no. 1, June 2018, pp. 160-8, https://www.tci-thaijo.org/index.php/reru/article/view/164870.