@book{118,
	author = { Heckard, Robert F. and Heckard, R. F.},
	title = {Statistics /},
	publisher = {Brooks/Cole, Cengage Learning,},
	year = {2012.},
	address = {Australia ;},
	edition = {Fourth edition},
	url = {http://www.loc.gov/catdir/toc/fy12pdf01/2010931695.html}
}