Cao, Waixiang https://orcid.org/0000-0003-2434-7300
Zhang, Zhimin
Funding for this research was provided by:
NSFC (11501026)
NSF (DMS-1419040)
NSFC (1147103, 91430216)
the Fundamental Research Funds for the Central Universities (No. 2017NT10)
NSAF (1530401)
Article History
Received: 31 January 2018
Revised: 3 June 2018
Accepted: 4 June 2018
First Online: 8 June 2018