Shokeralla, A. A. ., M. E. . Qurashi, R. Y. . Mekki, and M. S. . Ali. “The Effect of Symptoms on the Survival Time of Coronavirus Patients in the Sudanese Population”. International Journal of Statistics in Medical Research, vol. 12, Dec. 2023, pp. 249-56, doi:10.6000/1929-6029.2023.12.29.