Baird, . P. D. (1964). The Polar World. Longmans.
Cita Chicago (17th ed.)Baird, Patrick D. The Polar World. London: Longmans, 1964.
Cita MLA (9th ed.)Baird, Patrick D. The Polar World. Longmans, 1964.
Atenció: Aquestes cites poden no estar 100% correctes.