Dai, Shibin
Li, Bo
Lu, Jianfeng
Funding for this research was provided by:
Directorate for Mathematical and Physical Sciences (DMS-1411438, DMS-1620486)
National Science Foundation (DMS-1319731, DMS-1454939)
Article History
Received: 17 June 2016
Accepted: 21 July 2017
First Online: 18 August 2017