@book{601,
	author = {Blalock, Hubert M. and Naves, Juan},
	title = {Estadística social},
	publisher = {Fondo de Cultura Económica},
	year = {1983},
	series = {Sección de obras de sociología},
	address = {México, D.F.},
	edition = {2ª ed.}
}