@book{67048,
	author = {Langer, R. H. M. and Hill, G. D.},
	title = {Agricultural plants /},
	publisher = {Cambridge University Press,},
	year = {1991.},
	address = {New York :},
	edition = {2nd ed.},
	url = {http://www.loc.gov/catdir/description/cam021/91002246.html}
}