@book{67424,
	author = {Hussen, Ahmed M.},
	title = {Principles of environmental economics /},
	publisher = {Routledge,},
	year = {2004.},
	address = {London :},
	edition = {2nd ed.},
	url = {http://www.loc.gov/catdir/enhancements/fy0664/2003058501-d.html}
}