1School of Economics and Management, Tsinghua University, Beijing, 100084, China
2Donlinks School of Economics and Management, University of Science and Technology Beijing,
Beijing, 100083, P.R. China
Submission date: 2017-04-06
Final revision date: 2017-06-28
Acceptance date: 2017-07-11
Online publication date: 2018-01-08
Publication date: 2018-01-26
Pol. J. Environ. Stud. 2018;27(2):557–564