Abro, Falak, et al. “Epidemiology, Clinical Characteristics and Outcome of COVID-19 in Pediatric Patients Admitted at Aga Khan University Hospital, Karachi”. Pakistan Journal of Medical Research, vol. 60, no. 3, Oct. 2021, pp. 98-103, https://www.pjmr.org.pk/index.php/pjmr/article/view/231.