Steine, I M
Zayats, T
Stansberg, C
Pallesen, S
Mrdalj, J
Håvik, B
Soulé, J
Haavik, J
Milde, A M
Skrede, S
Murison, R
Krystal, J
Grønli, J
Article History
Received: 28 August 2016
Revised: 17 October 2016
Accepted: 20 October 2016
First Online: 13 December 2016
Competing interests
: The authors declare no conflict of interest.