@book{47939,
	author = {United Nations. Economic Commission for Europe},
	title = {ECE symposium on problem relating to environment},
	publisher = {Economic Commission for Europe},
	year = {1971},
	address = {New York},
	note = {Organised by United Nations Economic Commission for Europe and held from 2 to 15 May, 1971 in Prague (Czechoslovakia)with a study to us to the region of Ostrava (Czechoslovakia)and Katowice (Poland)}
}