Prakobvorakan, Bunyakon, Adisorn Naowanondha, and Somboon Tanya. “Development of the Instructional Model to Enhance Learning Happiness of Junior High School Students”. Ratchaphruek Journal 21, no. 1 (March 28, 2023): 137–151. accessed August 26, 2026. https://so05.tci-thaijo.org/index.php/Ratchaphruekjournal/article/view/260873.