Estudillo, H. M., and N. Mhunpiew. “The Development of a Strategic Leadership Model for Teacher Instructional Competencies at the Private Higher Education Institutions in Mindanao, Philippines”. Scholar: Human Sciences, vol. 13, no. 1, May 2021, pp. 121-37, http://www.assumptionjournal.au.edu/index.php/Scholar/article/view/5453.