@book{52745,
	author = {Gutiérrez Pulido, Humberto, and Vara Salazar, Román de la,},
	title = {Control estadístico de calidad y seis sigma /},
	publisher = { McGraw-Hill Interamericana,},
	year = {2009.},
	address = {Mexico :},
	edition = {2a edición.}
}