Cita APA (7a ed.)

Friedman, H., & Morrison, P. (1975). The amazing Universe. National Geographic Society.

Cita Chicago Style (17a ed.)

Friedman, Herbert, y Philip Morrison. The Amazing Universe. Washington: National Geographic Society, 1975.

Cita MLA (9a ed.)

Friedman, Herbert, y Philip Morrison. The Amazing Universe. National Geographic Society, 1975.