Zhao, Z
Xu, J
Chen, J
Kim, S
Reimers, M
Bacanu, S-A
Yu, H
Liu, C
Sun, J
Wang, Q
Jia, P
Xu, F
Zhang, Y
Kendler, K S
Peng, Z
Chen, X
Article History
Received: 21 May 2013
Revised: 23 May 2014
Accepted: 17 June 2014
First Online: 12 August 2014
Competing interests
: The authors declare no conflict of interest.