Kaiwong P, Chinatangkul C, Chaisirithanya K. Development of Happiness at Work Indicators of School Administrators in the Primary Educational Service Area Office in the Central Region. SDU. Grad. J. [internet]. 2021 Oct. 15 [cited 2025 Apr. 9];17(3):21-39. available from: https://so19.tci-thaijo.org/index.php/SDUGSAJ/article/view/365