@book{28054,
	author = {Wadsworth, Harrison M. and Stephens, Kenneth S.},
	title = {Modern methods for quality control and improvement /},
	publisher = {Wiley,},
	year = {1986.},
	address = {New York :},
	url = {http://www.loc.gov/catdir/toc/onix03/85020285.html}
}