TY - JOUR T1 - Soil nitrous oxide and nitric oxide emissions as indicators of the exceedance of critical loads of atmospheric nitrogen deposition in semi-natural ecosystems JF - Environmental Pollution Y1 - 1998 A1 - Skiba, U. A1 - Sheppard, L.J. A1 - Pitcairn, C.E.R. A1 - Leith, I.D. A1 - Crossley, A. A1 - van Dijk, S. A1 - Kennedy, V.J. A1 - Fowler, D. VL - 102 IS - S1 ER -