Princess Antoinette, Baroness of Massy

Authentic autographed vintage first day cover hand signed by Princess Antoinette of Monaco, Baroness of Massy, a non-dynastic member of the princely family of Monaco and the elder sister of the late Prince Rainier III and aunt of Albert II, Prince of Monaco. Her parents were Prince Pierre, Duke of Valentinois and Princess Charlotte, Duchess of Valentinois.