@book{24632,
	author = {Clapp, Frederick G.},
	title = {Economic geology of the Amity quadrangle, eastern Washington County, Pennsylvania /},
	publisher = {Govt. Print. Off.,},
	year = {1907.},
	series = {U.S. Geological survey. Buletin},
	address = {Washington,},
	note = {Subject series: A, Economic geology, 86; B, Descriptive geology, 105.}
}