@book{36040,
	author = {Malthus, T. R. and Gilbert, Geoffrey,},
	title = {An essay on the principle of population /},
	publisher = {Oxford University Press,},
	year = {1999.},
	series = {Oxford world's classics},
	address = {New York :},
	url = {http://www.loc.gov/catdir/enhancements/fy0608/00267065-d.html}
}