APA (7th ed.) Citation

Sagan, C., & Druyan, A. (1997). Comet (1st Ballantine Books ed.). Ballantine Books.

Chicago Style (17th ed.) Citation

Sagan, Carl, and Ann Druyan. Comet. 1st Ballantine Books ed. New York: Ballantine Books, 1997.

MLA (9th ed.) Citation

Sagan, Carl, and Ann Druyan. Comet. 1st Ballantine Books ed. Ballantine Books, 1997.

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