APA (7th ed.) Citation

Pius XI. Papst. (1938). Sixteen encyclicals of His Holiness Pope Pius XI: 1926 - 1937. National Catholic Welfare Conference.

Chicago Style (17th ed.) Citation

Pius XI. Papst. Sixteen Encyclicals of His Holiness Pope Pius XI: 1926 - 1937. Washington, DC: National Catholic Welfare Conference, 1938.

MLA (9th ed.) Citation

Pius XI. Papst. Sixteen Encyclicals of His Holiness Pope Pius XI: 1926 - 1937. National Catholic Welfare Conference, 1938.