A Abdalla, S. ., I. . Ali Ishag, and M.-K. . A Ahmed. “Goat Production System in Peri-Urban Areas of Khartoum State, Sudan”. Scientific Journal of Animal Science, vol. 1, no. 6, Dec. 2012, pp. 183-91, http://sjournals.com/index.php/sjas/article/view/1097.