Ratikainen, Irja I. http://orcid.org/0000-0001-9935-7998
Kokko, Hanna http://orcid.org/0000-0002-5772-4881
Article History
Received: 15 March 2018
Accepted: 14 January 2019
First Online: 1 February 2019
Competing interests
: The authors declare no competing interests.