31 For Our part, We confirm and ratify the grants of sacred indulgences made in years past in favor of the faithful who spend the month of October in the manner We have prescribed. Because of your authority and zeal, Venerable Brethren, We know that the Catholic people will be fired with devotion and holy emulation in venerating through the Rosary, the Blessed Virgin, Help of Christians.
Source: Magnae Dei Matris (Vatican.va)