1. College of Economics and Management, Hefei Normal University, Hefei 230601, China
2. School of Geography and Tourism, Anhui Normal University, Wuhu 241002, China
3. Department of Economics, Government Graduate College Kot Sultan, Kot Sultan 31650, Pakistan
4. Department of Economics, University of Layyah, Layyah 31200, Pakistan
5. College of Economics and Management, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
6. School of Management, Jiangsu University, Zhenjiang 212013, China