@book{8442,
	author = {Lenski, Gerhard and Nolan, Patrick.Lenski, Jean.},
	title = {Sociedades Humanas :},
	publisher = {McGraw Hill Interamericana, },
	year = {1997},
	address = {México, D.F:},
	edition = {Séptima edición},
	note = {Incluye indice.}
}