@book{500,
	author = {Sevenair, John. and Burkett, Allan R.},
	title = {Introductory chemistry :},
	publisher = {Wm.C. Brown Publishers,},
	year = {c1997.},
	address = {Dubuque, IA :},
	edition = {1st ed.},
	url = {http://www.loc.gov/catdir/description/mh022/96038217.html}
}