APA (7th ed.) Citation

Catholic Church. Pope (1922-1939 : Pius XI) & Pius XI, P. Why a retreat?: "Mens nostra," the encyclical of Pope Pius XI on Laymen's retreats. Paulist Press.

Chicago Style (17th ed.) Citation

Catholic Church. Pope (1922-1939 : Pius XI) and Pope Pius XI. Why a Retreat?: "Mens Nostra," the Encyclical of Pope Pius XI on Laymen's Retreats. New York: Paulist Press.

MLA (8th ed.) Citation

Catholic Church. Pope (1922-1939 : Pius XI) and Pope Pius XI. Why a Retreat?: "Mens Nostra," the Encyclical of Pope Pius XI on Laymen's Retreats. Paulist Press.