Farhadfar, Mozhgan, delkhosh kasmayi, abolghasem, Safari, Mahmoud. “Providing a Model to develop a model for school principals based on a competency-based approach  (Case Study: Tehran Secondary School.”  Quarterly Journal of Training and Development of Human Resources, vol. 8, no. 30, 2021, pp. 73-108. 10.52547/istd.31103.8.30.73