@book{18674,
	author = {Welty, Eberhard },
	title = {La encíclica social del Papa Juan XXIII Mater et Magistra},
	publisher = {Herder, },
	year = {c1963},
	address = {Barcelona : },
	edition = {1 ed.},
	note = {Introducción y comentario histórico doctrinal por Eberhard Welty}
}