@book {Tucker1994BI,
	title = {Birds in Europe: population estimates, trends and conservation status},
	year = {1994},
	pages = {600},
	publisher = {BirdLife International},
	organization = {BirdLife International},
	address = {Cambridge, UK},
	author = {Tucker, G.~M. and Heath, M.~F. and Tomialojc, L. and Grimmett, R.~F.~A.}
}