@book{3721,
	author = {Callan, Scott. and Thomas, Janet M.},
	title = {Environmental economics & management :},
	publisher = {Thomson/South-Western,},
	year = {c2007.},
	address = {Mason, OH :},
	edition = {4th ed.},
	url = {http://www.loc.gov/catdir/toc/fy0705/2006902916.html}
}