@book{18720,
	author = {International Union of Geological Sciences. and Hedberg, Hollis Dow,},
	title = {International stratigraphic guide :},
	publisher = {Wiley,},
	year = {c1976.},
	address = {New York :},
	note = {Includes index.},
	url = {http://www.loc.gov/catdir/toc/fy1002/75033086.html}
}