Kruit, H
Heikinheimo, O
Ulander, V-M
Aitokallio-Tallberg, A
Nupponen, I
Paavonen, J
Rahkonen, L
Article History
Received: 20 October 2015
Revised: 5 March 2016
Accepted: 7 March 2016
First Online: 14 April 2016
Competing interests
: The authors declare no conflict of interest.