@book{12196,
	author = {ECE Symposium on Problems Relating to Environment and United Nations.},
	title = {Proceedings and documentation of the symposium organized by the United Nations Economic Commission for Europe and held from 2 to 15 May 1971 in Prague (Czechoslovakia)},
	publisher = {United Nations},
	year = {1971.},
	address = {New York},
	note = {"United Nations publication. Sales number: E.71.II.E.6."}
}