Aekanakha, C., and tosaporn mahamud. “Factors Influencing the Core Competencies of Government Officials under the Department of Permanent Secretary for Bangkok”. Chophayom Journal, vol. 32, no. 1, June 2021, pp. 52-73, https://so01.tci-thaijo.org/index.php/ejChophayom/article/view/245784.