1. Graduate School of Education and Institute of Economics of Education, Peking University, Beijing, P.R. China
2. School of Applied Economics, Renmin University of China, Beijing, P.R. China
3. School of Mathematics and Statistics, Beijing Institute of Technology, Beijing, P.R. China
4. School of Management and Economics, Beijing Institute of Technology, Beijing, P.R. China
5. Center for Energy and Environmental Policy Research, Beijing Institute of Technology, Beijing, P.R. China
6. Faculty of Management Sciences, Department of Business Administration, ILMA University, Karachi, Pakistan
7. Beijing Key Laboratory of Energy Economics and Environmental Management, Beijing, P.R. China
8. Sustainable Development Research Institute for Economy and Society of Beijing, Beijing, P.R. China
9. Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing, P.R. China