APA (7e ed.) Bronvermelding

Asimov, I. (1989). Frontiers: New discoveries about man and his planet, outer space, and the universe. Plume.

Chicago (17e ed.) Bronvermelding

Asimov, Isaac. Frontiers: New Discoveries About Man and His Planet, Outer Space, and the Universe. New York: Plume, 1989.

MLA (9e ed.) Bronvermelding

Asimov, Isaac. Frontiers: New Discoveries About Man and His Planet, Outer Space, and the Universe. Plume, 1989.