Zhang, Shan
Liu, Zuhan
Funding for this research was provided by:
National Natural Science Foundation of China (11371310)
China Postdoctoral Science Foundation (2014M551621)
Postdoctoral Research Project of Jiangsu Province (1302043C)
Article History
Received: 22 July 2014
Accepted: 13 May 2015
First Online: 2 June 2015
Change Date: 15 May 2018
Change Type: Correction
Change Details: The authors would like to report a mistake in the proof of Theorem 4.1 in [3].