@book{22221,
	author = {Rey de Castilla y León, Alfonso X and Peña, Margarita.},
	title = {Alfonso el sabio : Antología },
	publisher = {Porrúa },
	year = {2000.},
	series = {Sepan cuantos; },
	address = {México },
	edition = {5a ed.},
	note = {Incluye índice}
}