@book{143221,
	author = {Vázquez Cruz, Ruperto},
	title = {Estadística elemental},
	publisher = {Editorial Universitaria},
	year = {1974},
	address = {Río Piedras, P.R.},
	edition = {6. ed.},
	note = {Publicaciones de la Facultad de Administración Comercial.}
}