Sonam, et al. “A Retrospective Comparative Study Of Covid-19 Mortality In First, Second And Third Wave Of Pandemic In District Sonipat, Haryana”. International Journal of Allied Medical Sciences and Clinical Research, vol. 11, no. 1, Feb. 2023, pp. 47-54, doi:10.61096/ijamscr.v11.iss1.2023.47-54.