@book{121798,
	author = {Van Helden, Albert.},
	title = {Huygens's ring, Cassini's division, and Saturn's children /},
	publisher = {Smithsonian Institution Libraries,},
	year = {c2006.},
	series = {Dibner Library lecture},
	address = {Washington, D.C. :},
	note = {"27 October 2004".}
}