Hagen, Knut http://orcid.org/0000-0003-2111-8895
Åsberg, Anders Nikolai
Uhlig, Benjamin L.
Tronvik, Erling
Brenner, Eiliv
Stjern, Marit
Helde, Grethe
Gravdahl, Gøril Bruvik
Sand, Trond
Article History
Received: 14 February 2018
Accepted: 14 March 2018
First Online: 20 March 2018
Competing interests
: The authors declare that they have no competing interests..
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.