@article {1610,
	title = {Biomonitoring methods for assessing the impacts of nitrogen pollution: refinement and testing},
	year = {2005},
	institution = {JNCC},
	issn = {386},
	author = {Leith, I. and van Dijk, N. and Pitcairn, C.E.R. and Wolseley, P.A. and Whitfield, C.P. and Sutton, M.A.}
}
