S. S. Ahmed, M. A. Soghaier, S. Mohammed, H. S. Khogali, M. M. Osman, and A. M. Abdalla, “Concomitant outbreaks of yellow fever and hepatitis E virus in Darfur States, Sudan, 2012”, J Infect Dev Ctries, vol. 10, no. 01, pp. 24–29, Jan. 2016.