Cita APA

National Geographic Maps (Firms), National Geographic Society, Johns, C., & Carroll, A. (2005). Europe. Washington, D.C.: National Geographic Society.

Citación estilo Chicago

National Geographic Maps (Firms), National Geographic Society, Chris Johns, y Allen Carroll. Europe. Washington, D.C.: National Geographic Society, 2005.

Cita MLA

National Geographic Maps (Firms), National Geographic Society, Chris Johns, y Allen Carroll. Europe. Washington, D.C.: National Geographic Society, 2005.