APA (7th ed.) Zitazioa

Steel, D. (1995). Rogue asteroids and doomsday comets: The search for the million megaton menace that threatens life on earth. Wiley.

Chicago Style (17th ed.) Zitazioa

Steel, Duncan. Rogue Asteroids and Doomsday Comets: The Search for the Million Megaton Menace That Threatens Life on Earth. New York: Wiley, 1995.

MLA (9th ed.) Zitazioa

Steel, Duncan. Rogue Asteroids and Doomsday Comets: The Search for the Million Megaton Menace That Threatens Life on Earth. Wiley, 1995.