APA (7th ed.) Citation

Pius IX, P. (1952). Apostolic letter of Pope Pius IX to Protestants and other non-Catholics. Graymoor Press.

Chicago Style (17th ed.) Citation

Pius IX, Pope. Apostolic Letter of Pope Pius IX to Protestants and Other Non-Catholics. Peekskill, N.Y.: Graymoor Press, 1952.

MLA (8th ed.) Citation

Pius IX, Pope. Apostolic Letter of Pope Pius IX to Protestants and Other Non-Catholics. Graymoor Press, 1952.

Warning: These citations may not always be 100% accurate.