@article {599,
	title = {Effects of simulated nitrogen rich and acid rain on the nitrogen-fixing lichen Peltigera aphthosa (L.) Willd. },
	journal = {New Phytologist},
	volume = {120},
	year = {1992},
	pages = {99-103},
	author = {Hallbdcken, L. and Kellner, O.}
}
