Cita APA

Fisher, R. M., & National Geographic Society. (1991). Heartland of a continent: America's plains and prairies. Washington: National Geographic Society.

Citación estilo Chicago

Fisher, Ronald M., y National Geographic Society. Heartland of a Continent: America's Plains and Prairies. Washington: National Geographic Society, 1991.

Cita MLA

Fisher, Ronald M., y National Geographic Society. Heartland of a Continent: America's Plains and Prairies. Washington: National Geographic Society, 1991.