Ujjan, Ikram Din. “Covid-19: Factors for Global Variations in Disease Severity and Mortality”. Journal of Liaquat University of Medical & Health Sciences 19, no. 03 (October 1, 2020): 150–151. Accessed November 24, 2024. http://ojs.lumhs.edu.pk/index.php/jlumhs/article/view/389.