Koskela, Erkki (contributor); Ollikainen, Markku (contributor) - 2004 - [Elektronische Ressource]
) Department of Economics, P.O. Box 17 (Arkadiankatu 7), Fin-00014 University
of Helsinki, Finland , E-mail: erkki ….koskela@helsinki.fi
2) Department of Economics and Management, P.O. Box 27, Fin-00014 University
of Helsinki, Finland. E-mail: markku ….ollikainen@helsinki.fi
3) Faculty of Forestry. University of Joensuu. P.O. Box 111, FIN-80101 Joensuu,
Finland. E-mail: timo …