@book{27433,
	author = {Butler, B. S. and Wilson, Eldred, and Geological Survey (U.S.)},
	title = {Geology and ore deposits of the Tombstone district, Arizona,},
	publisher = {University of Arizona},
	year = {[1938]},
	series = {Geological series,},
	address = {Tucson, Ariz.,},
	note = {University of Arizona bulletin, v. 9, no. 1, January, l938.}
}