@proceedings {222,
	title = {Nitrogen eutrophication and critical load for nitrogen based upon changes in flora and fauna in (semi)-natural terrestrial ecosystems},
	year = {1993},
	pages = {pp. 111-159},
	publisher = {Nordic Council of Ministers, Copenhagen, Denmark},
	address = {L{\"o}keberg, Sweden},
	author = {Bobbink, R. and Boxman, D. and Fremstad, E. and Heil, G. and Houdijk, A. and Roelofs, J.}
}
