@Article{acp-8-655-2008, AUTHOR = {Hõrrak, U. and Aalto, P. P. and Salm, J. and Komsaare, K. and Tammet, H. and Mäkelä, J. M. and Laakso, L. and Kulmala, M.}, TITLE = {Variation and balance of positive air ion concentrations in a boreal forest}, JOURNAL = {Atmospheric Chemistry and Physics}, VOLUME = {8}, YEAR = {2008}, NUMBER = {3}, PAGES = {655--675}, URL = {http://www.atmos-chem-phys.net/8/655/2008/}, ISSN = {1680-7316} }