Cita APA (7a ed.)
Grosvenor, M. B. National Geographic: Vol. 139, no. 4, April 1971. National Geographic Society.
Cita estilo Chicago (17a ed.)
Grosvenor, Melville Bell. National Geographic: Vol. 139, No. 4, April 1971. Washington, EUA: National Geographic Society.
Cita MLA (9a ed.)
Grosvenor, Melville Bell. National Geographic: Vol. 139, No. 4, April 1971. National Geographic Society.
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