@book{180557,
	author = {Powars, David S.     },
	title = {The effects of the Chesapeake Bay impact crater on the geologic framework and the correlation of hydrogeologic units of southeastern Virginia, south of the James River},
	publisher = {U.S. Dept. of the Interior, U.S. Geological Survey},
	year = {2000.},
	address = {Reston, Va.}
}