Gacharoen, Natthiya, and Laddawan Petchroj. 2023. “Leadership in the 21st Century for School Administrators Under the Secondary Educational Service Area Office Nonthaburi”. Journal of Humanities and Social Sciences, Rajapruk University 9 (3):52-69. https://so03.tci-thaijo.org/index.php/rpu/article/view/274233.