อินทัศสิงห์ณ. (2019). School Administrative Guideline for Developing the 12 Nation Main Values of Opportunity Expansion School Under the Uttaradit Primary Education Area Office 2. KASALONGKHAM RESEARCH JOURNAL, 13(1), 59-69. Retrieved from https://www.tci-thaijo.org/index.php/ksk/article/view/181695