So-Oabeb , J. H. S., and A. du Plessis. “Challenges Faced by Namibian School Principals and Heads of Departments in the Professional Development of School Teachers”. Namibia Educational Reform Forum Journal, vol. 32, no. 2, Oct. 2024, pp. 117-29, https://journals.nied.edu.na/index.php/nerfj/article/view/155.