Motu Proprio (Leo XIII) Placere Nobis – Motu Proprio (Leo XIII – Jan. 18, 1880) Augustum Sanctissimumque – Motu Proprio of the Supreme Pontiff on the Rules of the Vatican Library (Leo XIII – Oct. 1, 1888) Ea Animi Sollicitudo – Motu Proprio of the Supreme Pontiff Suppressing the Vacabili (Leo XIII – July 4, 1898)
