1. Abdel Karim, I., 2002. The Impact of the Uruguay Round Agreement on Sudan’s Agricultural Trade. Published Ph.D. Dissertation, Humboldt University, Berlin.
2. Armington, P., 1969. A Theory of Demand for Products Distinguished by Place of Production. IMF Staff Papers.
3. Bank of Sudan, 2007. Annual Report. Khartoum, Sudan.
4. COMESA, 2004. Establishment and Membership. (Available at: http://www.itcilo.it/actrav/actravenglish/telearn/global/ilo/blokit/comesa-htm).
5. COMESA, 2007. COMESA in Brief. (http://www.COMESA.int).