@book{17509,
	author = {Ojakangas, Richard W. and Darby, David G.,},
	title = {The earth, past & present /},
	publisher = {McGraw-Hill,},
	year = {c1976.},
	series = {McGraw-Hill earth science paperback series},
	address = {New York :},
	note = {Includes index.}
}