Vehus, T.
Roberg-Larsen, H.
Waaler, J.
Aslaksen, S.
Krauss, S.
Wilson, S. R.
Lundanes, E.
Article History
Received: 18 August 2016
Accepted: 28 October 2016
First Online: 29 November 2016
Competing interests
: The authors declare no competing financial interests.