@book{26672,
	author = {Lobeck, A. K.},
	title = {The geology and physiography of the Mammoth Cave national park,},
	publisher = {The Kentucky Geological survey,},
	year = {1928.},
	series = {Kentucky. Geological survey. Ser. VI. Pamphlet XXI},
	address = {Frankfort, Ky.,}
}