Kuba, K
Esser, P
Mehnert, A
Johansen, C
Schwinn, A
Schirmer, L
Schulz-Kindermann, F
Kruse, M
Koch, U
Zander, A
Kröger, N
Götze, H
Scherwath, A
Article History
Received: 28 April 2017
Revised: 6 July 2017
Accepted: 29 July 2017
First Online: 11 September 2017
Competing interests
: The authors declare no conflict of interest.