@book{173877,
	author = {Halphen, Louis},
	title = {Carlomagno y el imperio carolingio},
	publisher = {Union Tipografica Editioral Hispano Americana},
	year = {1955.},
	series = {La evolucion de la humanidad : sintesis colectiva},
	address = {Mexico},
	note = {Translation of: Charlemagne et l'empire Carolingien.}
}