@book{4944,
	author = {Heath, Margaret L. and Thomas, Veronica J.},
	title = {Patient controlled analgesia :},
	publisher = {Oxford University Press,},
	year = {c1993.},
	address = {Oxford ;},
	url = {http://www.loc.gov/catdir/enhancements/fy0603/93001605-d.html}
}