Duangtanoo, T., D. Thawinkarn, and W. Areerat. “Indicators Development for Constructive Culture in Opportunity Expansion School under Khon Kaen Primary Educational Service Area Office 1”. KKU Research Journal (Graduate Studies) Humanities and Social Sciences, vol. 7, no. 3, Nov. 2019, pp. 58-68, https://so04.tci-thaijo.org/index.php/gskkuhs/article/view/226952.