Feilchenfeldt, J
Varga, Z
Siano, M
Grabsch, H I
Held, U
Schuknecht, B
Trip, A
Hamaguchi, T
Gut, P
Balague, O
Khanfir, K
Diebold, J
Jochum, W
Shoji, H
Kushima, R
Wagner, D
Shimada, Y
Cats, A
Knuth, A
Moch, H
Aebi, S
Hofer, S
Article History
Received: 18 April 2015
Revised: 5 June 2015
Accepted: 2 July 2015
First Online: 27 August 2015
Change Date: 1 September 2015
Change Type: Update
Change Details: This paper was modified 12 months after initial publication to switch to Creative Commons licence terms, as noted at publication
Competing interests
: The authors declare no conflict of interest.