Onuh, (PhD), Samuel. “Coronavirus Pandemic and The Challenges of Oil Producing Economies in Africa: Nigeria And Angola In Comparative Perspective”. International Journal of Social Sciences and Humanities Invention 10, no. 08 (August 10, 2023): 7971–7977. Accessed July 3, 2024. http://valleyinternational.net/index.php/theijsshi/article/view/4611.