@book{24318,
	author = {Purington, Chester Wells,},
	title = {Methods and costs of gravel and placer mining in Alaska /},
	publisher = {Govt. Print. Off.,},
	year = {1905.},
	series = {U.S. Geological survey. Bulletin},
	address = {Washington,},
	note = {Subject series: A, Economic geology, 55.}
}