Ritschel, Vibeke
Shetelig, Christian
Seljeflot, Ingebjørg
Limalanathan, Shanmuganathan
Hoffmann, Pavel
Halvorsen, Sigrun
Arnesen, Harald
Eritsland, Jan
Andersen, Geir Øystein
Article History
Received: 5 July 2017
Accepted: 7 September 2017
First Online: 20 September 2017
Competing Interests
: The authors declare that they have no competing interests.