Dong, Hongjie http://orcid.org/0000-0003-2258-3537
Li, Haigang
Funding for this research was provided by:
Directorate for Mathematical and Physical Sciences (DMS-1056737, DMS-1600593)
National Natural Science Foundation of China (11571042, 11631002)
Fok Ying Tung Education Foundation (151003)
Article History
Received: 20 April 2016
Accepted: 17 August 2018
First Online: 24 August 2018
Conflict of Interest
: The authors declare that they have no conflict of interest.