Niittynen, Pekka http://orcid.org/0000-0002-7290-029X
Heikkinen, Risto K.
Luoto, Miska http://orcid.org/0000-0001-6203-5143
Article History
Received: 5 December 2017
Accepted: 21 September 2018
First Online: 22 October 2018
Competing interests
: The authors declare no competing interests.