Yesterday, for the Feast of St. Pius V in the calendar of the usus antiquior, Msgr. Guido Pozzo, Secretary of the Ecclesia Dei Commission, celebrated a Solemn Mass in the Borghese Chapel (Salus Populi Romani) of the Basilica of Santa Maria Maggiore in Rome -- the basilica where the the tomb of St. Pius V is found.
John Sonnen, as always, has the photos. Here are some of them.