เพ็งสง ศ. THE SEVANT LEADERSHIP OF SCHOOL ADMINISTRATORS UNDER PHATTHALUNG PRIMARY EDUCATIONAL SERVICE AREA OFFICE 1. ptujournal [internet]. 2020 Dec. 31 [cited 2026 Sep. 28];12(2):450-65. available from: https://so05.tci-thaijo.org/index.php/ptujournal/article/view/248230