Cita APA (7th ed.)

Irion, R. (2001). Galaxies: Island universes. Reader's Digest.

Cita Chicago (17th ed.)

Irion, Robert. Galaxies: Island Universes. Pleasantville: Reader's Digest, 2001.

Cita MLA (9th ed.)

Irion, Robert. Galaxies: Island Universes. Reader's Digest, 2001.