Zhang, Hui
Yan, Ming
Yin, Wotao
Funding for this research was provided by:
National Science Foundation (DMS-0748839)
National Science Foundation (ECCS-1028790)
National Science Foundation (CCF-0926127)
National Natural Science Foundation of China (11501569)
National Natural Science Foundation of China (61072118)
Article History
Received: 30 October 2014
Accepted: 23 June 2016
First Online: 6 July 2016