Hietavala, E-M
Stout, J R
Hulmi, J J
Suominen, H
Pitkänen, H
Puurtinen, R
Selänne, H
Kainulainen, H
Mero, A A
Article History
Received: 19 June 2014
Revised: 15 August 2014
Accepted: 7 September 2014
First Online: 10 December 2014
Competing interests
: HP has a commercial association with Honkatarhat Ltd, Kyröntarhat Ltd and Mykora Ltd. He accepts full responsibility for the implementation and publication of this study. He also had full access to all the data. The remaining authors declare no conflict of interest.