@book{25450,
	author = {Marshall, R. B. and Virginia Geological Survey.},
	title = {Results of spirit leveling in Virginia, 1900 to 1913, inclusive /},
	publisher = {Govt. Print. Off.,},
	year = {1914.},
	series = {U.S. Geological survey. Bulletin 562},
	address = {Washington,},
	note = {Includes index.}
}