@book{30438,
	author = {Ruddiman, W. F.},
	title = {Plows, plagues, and petroleum :},
	publisher = {Princeton University Press,},
	year = {c2005.},
	address = {Princeton, N.J. :},
	url = {http://www.loc.gov/catdir/enhancements/fy0654/2004062444-d.html}
}