Tiengyoo, K. ., S. . Sotaro, and S. Thaithae. “Second-Order Confirmatory Factor Analysis of 21st Century Mathematics Teaching Predicament Among Secondary Mathematics Teachers in Secondary Educational Service Area Office Lopburi”. Science Essence Journal, vol. 40, no. 1, Apr. 2024, pp. 1-17, https://ejournals.swu.ac.th/index.php/sej/article/view/15881.