Cheng, Hai
Edwards, R. Lawrence
Sinha, Ashish
Spötl, Christoph
Yi, Liang
Chen, Shitao
Kelly, Megan
Kathayat, Gayatri
Wang, Xianfeng
Li, Xianglei
Kong, Xinggong
Wang, Yongjin
Ning, Youfeng
Zhang, Haiwei
Article History
Received: 26 January 2016
Accepted: 18 May 2016
First Online: 29 June 2016
Competing interests
: The authors declare no competing financial interests.