@Book{FIL20140000463, title = "Bernal D\'{\i}az del Castillo", author = "Unamuno, Miguel de, 1864-1936. Bernal D\'{\i}az del Castillo. 1921. Espa\~{n}ol", URL = "http://www.larramendi.es/es/consulta/registro.do?id=13481", year = "2011", }