@article {251,
	title = {Soil nitrous oxide and nitric oxide emissions as indicators of the exceedance of critical loads of atmospheric nitrogen deposition in semi-natural ecosystems},
	journal = {Environmental Pollution},
	volume = {102},
	year = {1998},
	pages = {457-461},
	author = {Skiba, U. and Sheppard, L.J. and Pitcairn, C.E.R. and Leith, I.D. and Crossley, A. and van Dijk, S. and Kennedy, V.J. and Fowler, D.}
}
