@book{21,
	author = {Papalia, Diane E. and Olds, Sally Wendkos.},
	title = {Psicología del desarrollo de la infancia a la adolescencia },
	publisher = {McGraw Hill,},
	year = {2009. },
	series = {PSICOLOGIA},
	address = {México :},
	edition = {11a ed.},
	note = {Traducción de: A child's world : infancy through adolescence. }
}