@book{36008,
	author = {United States.},
	title = {Wages and hours of labor in the Portland cement industry, 1929 ... January, 1931.},
	publisher = {U.S. Govt. Print. Off.,},
	year = {1931.},
	address = {Washington,},
	note = {At head of title: United States Department of Labor. W.N. Doak, secretary. Bureau of Labor Statistics. Ethelbert Stewart, commissioner.}
}