Trøstrup, C. H.
Christiansen, A. B.
Stølen, K. S.
Nielsen, P. K.
Stelter, R.
Article History
Accepted: 30 January 2019
First Online: 11 February 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors. The study is a literature review.