@book{15181,
	author = {Cunningham, William P. and Cunningham, Mary Ann.},
	title = {Principles of environmental science:},
	publisher = {McGraw-Hill,},
	year = {c2010.},
	address = {Dubuque, IA :},
	edition = {5th ed.},
	url = {http://www.loc.gov/catdir/toc/ecip0817/2008019443.html}
}