Schraut, K G
Jakob, S B
Weidner, M T
Schmitt, A G
Scholz, C J
Strekalova, T
El Hajj, N
Eijssen, L M T
Domschke, K
Reif, A
Haaf, T
Ortega, G
Steinbusch, H W M
Lesch, K P
Van den Hove, D L
Article History
Received: 20 August 2014
Accepted: 25 August 2014
First Online: 21 October 2014
Competing interests
: The authors declare no conflict of interest.