Encyclical letter of His Holiness, Pius XI, by Divine Providence Pope to our venerable brethren, the patriarchs, primates, archbishops, bishops and other ordinaries, in peace and communion with the Apostolic See concerning Catholic Action.

Eitemau Tebyg

• Encyclical letter of His Holiness Pius XI, by Divine providence, pope to our venerable brethren: the patriarchs, primates, archbishops, bishops and other ordinaries, in peace and communion with the Apostolic See, and to all the faithful of the Catholic world, on reconstructing the social order and perfecting it conformably to the precepts of the Gospel, in commemoration of the fortieth anniversary of the encyclical "Rerum novarum."
  Wedi'i Greu: (1940)
• Encyclical letter (Divini Redemptoris) of His Holiness Pius XI to his venerable brethren the patriarchs, primates, archbishops, bishops, and other ordinaries in peace and communion with the Apostolic See on atheistic communism.
  Wedi'i Greu: (1946)
• Encyclical letter of Pope Pius XI on reconstructing the social order.
  Wedi'i Greu: (1939)
• Encyclical letter of Our Most Holy Lord Pius IX : by divine providence Pope, to all patriarchs, primates, archbishops, and other ordinaries in the grace and communion of the Apostolic See
  gan: Pius IX, Pope, 1792-1878
  Wedi'i Greu: (1874)
• The light of truth : concerning the celebration of the fifteenth centenary of the Oecumenical Council of Ephesus : encyclical letter (Lux veritatis) of His Holiness, Pope Pius XI : (Vatican Press translation) : issued December 25, 1931.
  Wedi'i Greu: (1932)