@book{93,
	author = {Ludwig, John A. and Reynolds, James F.,},
	title = {Statistical ecology :},
	publisher = {Wiley,},
	year = {c1988.},
	address = {New York :},
	note = {Requisitos del sistema para el disco del ordenador: IBM PC o compatible; MS-DOS o PC-DOS 2.0 o superior.},
	url = {http://www.loc.gov/catdir/toc/onix01/87026348.html}
}