@book{123101,
	author = {Williams, C. J. F.},
	title = {What is existence? /},
	publisher = {Clarendon Press ;},
	year = {1981.},
	series = {Clarendon library of logic and philosophy},
	address = {Oxford :},
	note = {Includes index.},
	url = {http://www.loc.gov/catdir/enhancements/fy0603/80041967-d.html}
}