1. Department of Economics and Development Studies, Faculty of Economics, Universitas Terbuka, Banten, Indonesia
2. Department of Economics, Faculty of Economics and Business, Universitas Airlangga, Surabaya, Indonesia
3. Department of Economics, Faculty of Social and Management Sciences, Federal University Birnin Kebbi, Kebbi, Nigeria
4. School of Economics, Universiti Kebangsaan Malaysia, Bangi, Malaysia