Li, Zhongyan http://orcid.org/0000-0002-0132-730X
Han, Deguang
Funding for this research was provided by:
The National Natural Science Foundation of China; (Grant No. 11571107)
NSF under the grants (DMS-1403400 and DMS-1712602)
Article History
Received: 12 October 2017
Accepted: 2 June 2018
First Online: 28 June 2018