@book{177164,
	author = {United Nations.},
	title = {Indexes to the International standard industrial classification of all economic activities /},
	publisher = {United Nations,},
	year = {1971.},
	series = {United Nations; Statistical Office; Statistical papers / M},
	address = {New York :},
	note = {United Nations [Document] ST/STAT/ser.M/4/rev. 1/add.1.}
}