Cita APA (7th ed.)

Bonner, M. G. (1944). Couriers of the sky; the story of pigeons. A. A. Knopf.

Cita Chicago (17th ed.)

Bonner, Mary Graham. Couriers of the Sky; the Story of Pigeons. New York: A. A. Knopf, 1944.

Cita MLA (9th ed.)

Bonner, Mary Graham. Couriers of the Sky; the Story of Pigeons. A. A. Knopf, 1944.