36 Meanwhile, for the good of souls, We grant, from the treasury of holy indulgences confided by God to Our custody, to all those who assist piously at the functions celebrated in honor of St. Francis, an indulgence of seven years and seven quarantines daily. On the last day of these functions, or on any other day one may choose, We grant, under the customary conditions, a plenary indulgence. In order to bestow a very special mark of Our affection on the Convent of the Sisters of the Visitation at Annecy, where the body of St. Francis rests - on the very altar over his body We have with great spiritual joy celebrated Mass - and on the Convent of Treviso where his heart is preserved, and on all other Visitation Convents, We grant during the functions which they will hold every month in thanksgiving to God, and over and above these days, on the twenty-eighth of December, but only for this particular year, to all who make the customary visits to their churches, the plenary indulgence, provided they confess and receive Holy Communion and pray according to Our intention.
Source: Rerum Omnium Perturbationem (Vatican.va)