Guivis Nkemgha University of Cape Town   guivis.nkemgha@uct.ac.za guivis.nkemgha@uct.ac.za guivis.nkemgha@uct.ac.za Cape Town, South Africa   nkemghazeufackguivis@yahoo.fr             JEL Areas: F1 : Trade: General O : Economic Development, Technological Change, and Growth