Kamber, C
Zimmerli, S
Suter-Riniker, F
Mueller, B U
Taleghani, B M
Betticher, D
Zander, T
Pabst, T
Article History
Received: 5 September 2014
Revised: 8 October 2014
Accepted: 10 October 2014
First Online: 19 January 2015
Competing interests
: The authors declare no conflict of interest.
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