@book{256043,
	author = {McKnight, Tom L. and Hess, Darrel.},
	title = {Physical geography :},
	publisher = {Pearson Prentice Hall,},
	year = {c2008.},
	address = {Upper Saddle River, NJ :},
	edition = {9th ed.},
	url = {http://www.loc.gov/catdir/toc/ecip078/2007000858.html}
}