Poolpokpol, A., and D. Parunggul . “The Relationship Between Instructional Leadership of School Administrators  and School Effectiveness in The Diocese of Ratchaburi”. Saengtham College Journal, vol. 12, no. 1, June 2020, pp. 106-31, https://so01.tci-thaijo.org/index.php/scj/article/view/245804.