Somsri, S., and S. Jusuwan. “The Development of Program to Enhance Servant Leadership of Schools Administrators of Educational Catholic Schools under Ubonrachatani Diocese”. Journal for Developing the Social and Community, vol. 7, no. 1, June 2020, pp. 315-28, https://so03.tci-thaijo.org/index.php/rdirmu/article/view/245126.