Ugwuegede, C. M., S. N. Okoli, and C. A. . Onumba. “Analysis of School Closure and Online Teaching-Learning in Higher Education Amid COVID-19 Pandemic”. International Academic Journal of Medical and Clinical Practice, vol. 6, no. 4, Dec. 2021, pp. 39-47, http://cirdjournals.com/index.php/iajmcp/article/view/607.