Tønne, Elin
Holdhus, Rita
Stansberg, Christine
Stray-Pedersen, Asbjørg
Petersen, Kjell
Brunner, Han G
Gilissen, Christian http://orcid.org/0000-0003-1693-9699
Hoischen, Alexander
Prescott, Trine
Steen, Vidar M
Fiskerstrand, Torunn
Article History
Received: 23 September 2014
Revised: 2 December 2014
Accepted: 6 January 2015
First Online: 4 March 2015
Competing interests
: The authors declare no conflict of interest.