@book{192949,
	author = {United States},
	title = {1997 economic census.},
	publisher = {U.S. Dept. of Commerce, Economics and Statistics Administration, U.S. Census Bureau},
	year = {2001.},
	address = {[Washington, D.C.]},
	note = {"Issued April 2001."},
	url = {http://www.census.gov/prod/ec97/97s56-sm.pdf}
}