Gajer, J M
Furdas, S D
GrĂ¼nder, A
Gothwal, M
Heinicke, U
Keller, K
Colland, F
Fulda, S
Pahl, H L
Fichtner, I
Sippl, W
Jung, M
Article History
Received: 21 July 2014
Accepted: 9 December 2014
First Online: 9 February 2015
Competing interests
: The authors declare no conflict of interest.