د. صلاح محمد ابراهيم أحمد, and محمد مسعود محمد ادريس. “The Impact of External Cash Flows on Economic Growth in Sudan During the Period (1990-2014)”. White Nile Journal for Studies and Research, no. 8, Sept. 2016, pp. 8-31, https://journals.wnu.edu.sd/index.php/wnjsr/article/view/197.