@article {1277, title = {Diagnostic indicators of elevated nitrogen deposition}, journal = {Environmental Pollution}, volume = {144}, year = {2006}, author = {Pitcairn, C.E.R. and Fowler D. and Leith, I.D. and Sheppard, L.J. and Tang, Y.S. and Sutton, M.A. and Famulari D.} }