1. School of Management and Economics Beijing Institute of Technology Beijing China
2. Centre for Energy and Environmental Policy Research Beijing Institute of Technology Beijing China
3. School of Economics and Management Beijing Forestry University Beijing China
4. School of Business Nanjing University of Information Science and Technology Nanjing China
5. Department of Economics Nasarawa State University Keffi Nasarawa Nigeria
6. Department of Statistics Federal University of Lafia Lafia Nasarawa Nigeria
7. Post Primary School Post Primary Schools Management Board Yola Adamawa Nigeria