@book{1764,
	author = {Downing, Douglas.},
	title = {Trigonometry:},
	publisher = {Barron's,},
	year = {2001.},
	address = {Hauppauge, NY :},
	edition = {3rd ed.},
	url = {http://www.loc.gov/catdir/enhancements/fy0630/00062157-d.html}
}