Cita APA (7a ed.)

North, R. (1969). Prophets for the 21st century. Gregorian.

Cita Chicago Style (17a ed.)

North, Robert. Prophets for the 21st Century. Rome: Gregorian, 1969.

Cita MLA (9a ed.)

North, Robert. Prophets for the 21st Century. Gregorian, 1969.