Iqbal, Iqbal Firdaus, et al. “Survival Analysis Of Health Rate Of Covid-19 Patients Using Kaplan-Meier Method At Islamic Hospital In Surabaya A. Yani”. Medical Technology and Public Health Journal , vol. 5, no. 2, Sept. 2022, pp. 250-7, doi:10.33086/mtphj.v5i2.3173.