Thayyil, J., A. Padmanabhan, A. Gangadharan, and N. Annikady. “Epidemiological Study of COVID-19 Mortality in a Tertiary Care Center of South India”. International Journal Of Community Medicine And Public Health, vol. 9, no. 11, Oct. 2022, pp. 4074-80, doi:10.18203/2394-6040.ijcmph20222640.