Giskeødegård, Guro F
Hansen, Ailin Falkmo
Bertilsson, Helena
Gonzalez, Susana Villa
Kristiansen, Kåre Andre
Bruheim, Per
Mjøs, Svein A
Angelsen, Anders
Bathen, Tone Frost
Tessem, May-Britt
Article History
Received: 29 May 2015
Revised: 28 October 2015
Accepted: 4 November 2015
First Online: 3 December 2015
Competing interests
: The authors declare no conflict of interest.