Adam, D., Ali, M., Ahmed, M., Banaga, A., Alrahman, A., & Alzain, E. (2015). HIGHLIGHTS ON THE HISTORY OF SMALLPOX EPIDEMIOLOGY AND ERADICATION IN THE SUDAN. International Journal of Research -GRANTHAALAYAH, 3(6), 128–136. https://doi.org/10.29121/granthaalayah.v3.i6.2015.3008