Vogel, Marc
Chumak, Andrii V.
Waller, Erik H.
Langner, Thomas
Vasyuchka, Vitaliy I.
Hillebrands, Burkard
von Freymann, Georg
Article History
Received: 17 November 2014
Accepted: 26 March 2015
First Online: 18 May 2015
Competing interests
: The authors declare no competing financial interests.