Authors
E Cheng-Guo
School of Economics and Management, Yanshan University, Qinhuangdao, China
Liren College, Yanshan University, Qinhuangdao, China
Quan-Lin Li
School of Economics and Management, Yanshan University, Qinhuangdao, China
Shiyong Li
School of Economics and Management, Yanshan University, Qinhuangdao, China