Cita APA (7th ed.)
Johns, C. (2014). National geographic: Defenders of the Amazon. National Geographic.
Cita Chicago (17th ed.)
Johns, Chris. National Geographic: Defenders of the Amazon. Washington: National Geographic, 2014.
Cita MLA (9th ed.)
Johns, Chris. National Geographic: Defenders of the Amazon. National Geographic, 2014.
Atenció: Aquestes cites poden no estar 100% correctes.