Väliranta, M.
Salonen, J. S.
Heikkilä, M.
Amon, L.
Helmens, K.
Klimaschewski, A.
Kuhry, P.
Kultti, S.
Poska, A.
Shala, S.
Veski, S.
Birks, H. H.
Article History
Received: 19 August 2014
Accepted: 27 February 2015
First Online: 10 April 2015
Competing interests
: The authors declare no competing financial interests.