Bjorn-Mortensen, K.
Soborg, B.
Koch, A.
Ladefoged, K.
Merker, M.
Lillebaek, T.
Andersen, A. B.
Niemann, S.
Kohl, T. A.
Article History
Received: 24 May 2016
Accepted: 19 August 2016
First Online: 12 September 2016
Competing interests
: The authors declare no competing financial interests.