Cita APA (7a ed.)
Shupe, J. F., & Allen, W. L. The Earth's Fractured Surface. National Geographic Society.
Cita estilo Chicago (17a ed.)
Shupe, John F., y William L. Allen. The Earth's Fractured Surface. Washington, EUA: National Geographic Society.
Cita MLA (9a ed.)
Shupe, John F., y William L. Allen. The Earth's Fractured Surface. National Geographic Society.
Precaución: Estas citas no son 100% exactas.