%0 Generic %D 1997 %T Long term effects of ammonium sulphate on Calluna vulgaris %A Uren, S.C. %A Ainsworth, N. %A Power, S. %A Cousins, D.A. %A Huxendurp, L.M. %A Ashmore, M.R. %B Journal of Applied Ecology %V 34 %P 208-216