%0 Report %D 2004 %T Effects of enhanced N deposition on Cladonia portentosa; results from a field manipulation study. %A Sheppard, L.I. %A Leith, I.D. %A Crossley, A. %B Lichens in a Changing Pollution Environment, English Nature Workshop %I English Nature %C Peterborough %P 51-62 %G eng