%0 Journal Article %J Environmental Pollution %D 1998 %T Soil nitrous oxide and nitric oxide emissions as indicators of the exceedance of critical loads of atmospheric nitrogen deposition in semi-natural ecosystems %A Skiba, U. %A Sheppard, L.J. %A Pitcairn, C.E.R. %A Leith, I.D. %A Crossley, A. %A van Dijk, S. %A Kennedy, V.J. %A Fowler, D. %B Environmental Pollution %V 102 %P 457-461 %N S1