@book{52169,
	author = {Walker, Samuel, and Katz, Charles M.},
	title = {The police in America :},
	publisher = {McGraw-Hill,},
	year = {2011.},
	address = {Dubuque, Iowa :},
	edition = {7th ed.},
	url = {http://www.loc.gov/catdir/enhancements/fy1005/2009045528-b.html}
}