@book{35586,
	author = {United States.},
	title = {Hours and earnings in anthracite and bituminous coal mining.},
	publisher = {Govt. Print. Off.,},
	year = {1921.},
	series = {Bulletin of the United States Bureau of Labor Statistics,},
	address = {Washington,},
	note = {At head of title:  U.S. Department of Labor.  James J. Davis, secretary.  Bureau of Labor Statistics.  Ethelbert Stewart, commissioner.}
}