@book{1846,
	author = {Martin, David, and Martin, David,},
	title = {Geographic information systems :},
	publisher = {Routledge,},
	year = {1996.},
	address = {London ;},
	edition = {2nd ed.},
	note = {Rev. ed. of: Geographic information systems and their socioeconomic applications. 1991.},
	url = {http://www.loc.gov/catdir/enhancements/fy0649/95015958-d.html}
}