1. Trade and Development Department, Faculty of Economic and Management Sciences, Potchefstroom Campus, North-West University, Potchefstroom 2520, South Africa
2. Department of Economics, Accounting and Finance, Faculty of Commerce, Human Sciences and Education, Namibia University of Science and Technology, Windhoek 9000, Namibia
3. Department of Economics and Mathematics, Faculty of Business Administration and Strategic Management, International University of Management, Windhoek 9000, Namibia