@book{14375,
	author = {Ravera, O. and European Ecological Symposium},
	title = {Terrestrial and aquatic ecosystems :},
	publisher = {Ellis Horwood,},
	year = {1991.},
	address = {New York :},
	note = {Papers from the Fifth European Ecological Symposium held at Siena, Italy, Sept. 25-29, 1989.}
}