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	volume = {107(3)},
	year = {2000},
	pages = {421-436},
	author = {Manninen, S. and Huttunen, S.}
}
@article {670,
	title = {Assessing the critical load of SO2 for Scots Pine in situ. },
	journal = {Environmental Pollution},
	volume = {93},
	year = {1996},
	pages = {27-38},
	author = {Manninen, S. and Huttunen, S. and Rautio, P. and Peramaki, P.}
}
