Kobkhuntod, J., Jainim, P. . and Phungphae, P. (2023) “DEVELOPMENT OF SOCIAL STUDIES TEACHING IN THE 21st CENTURY USING PROBLEM-BASED”, PNRU Academic Journal, 2(1), pp. 36–46. available at: https://so07.tci-thaijo.org/index.php/PNRU_ACA/article/view/1949 (accessed: 28 June 2025).