Du, Yu
Zhang, Zhimin
Funding for this research was provided by:
National Nature Science Foundation of China (11601026, 11471031)
National Nature Science Foundation of China (91430216)
NASF (U1530401)
Division of Mathematical Sciences (1419040)
Article History
Received: 28 May 2018
Revised: 12 November 2018
Accepted: 4 January 2019
First Online: 18 January 2019