Thain S, Mulkhien S. The development of 21st century teacher competencies in Yupparaj Wittayalai school, the secondary education area, Chiang Mai. . JMHR [Internet]. 2024 Mar. 31 [cited 2024 May 19];8(1):206-19. Available from: https://so04.tci-thaijo.org/index.php/JMHR/article/view/a014