Cita APA (7th ed.)

Aretin, K. O. (1970). The Papacy and the modern world. Weidenfeld & Nicolson.

Cita Chicago (17th ed.)

Aretin, Karl Otmar. The Papacy and the Modern World. London: Weidenfeld & Nicolson, 1970.

Cita MLA (9th ed.)

Aretin, Karl Otmar. The Papacy and the Modern World. Weidenfeld & Nicolson, 1970.