APA (7th ed.) Citation

Aguilar, D. A. (2013). Alien worlds: Your guide to extraterrestrial life. National Geographic.

Chicago Style (17th ed.) Citation

Aguilar, David A. Alien Worlds: Your Guide to Extraterrestrial Life. Washington, D.C.: National Geographic, 2013.

MLA (8th ed.) Citation

Aguilar, David A. Alien Worlds: Your Guide to Extraterrestrial Life. National Geographic, 2013.

Warning: These citations may not always be 100% accurate.