APA (7th ed.) Citation

Pastor, L., & Kerr, R. F. (1923). The history of the Popes: From the close of the Middle Ages. Herder Book.

Chicago Style (17th ed.) Citation

Pastor, Ludwig, and Ralph Francis Kerr. The History of the Popes: From the Close of the Middle Ages. St. Louis: Herder Book, 1923.

MLA (9th ed.) Citation

Pastor, Ludwig, and Ralph Francis Kerr. The History of the Popes: From the Close of the Middle Ages. Herder Book, 1923.