@book{18188,
	author = {Butzer, Karl W. and Hansen, Carl L. and Yale Prehistoric Nubia Expedition},
	title = {Desert and river in Nubia :},
	publisher = {University of Wisconsin Press,},
	year = {1968.},
	address = {Madison :},
	note = {Research conducted during the 1962-63 Yale Prehistoric Nubia Expedition.}
}