Cheng, Kelong
Wang, Cheng
Wise, Steven M.
Yue, Xingye
Funding for this research was provided by:
Division of Mathematical Sciences (1418689, 1418692)
National Natural Science Foundation of China (11271281)
China Scholarship Council (201408515169)
Article History
Received: 11 February 2016
Revised: 14 May 2016
Accepted: 19 May 2016
First Online: 31 May 2016