Haemmig, S
Baumgartner, U
Glück, A
Zbinden, S
Tschan, M P
Kappeler, A
Mariani, L
Vajtai, I
Vassella, E
Article History
Received: 11 March 2014
Revised: 28 March 2014
Accepted: 29 April 2014
First Online: 5 June 2014
Competing interests
: The authors declare no conflict of interest.