Cita APA (7th ed.)

HARTMANN, W. K. (1985). Astronomy the cosmic journey.-- Ed. 3. Wadsworth Pub. Co.

Cita Chicago (17th ed.)

HARTMANN, William K. Astronomy the Cosmic Journey.-- Ed. 3. Belmont: Wadsworth Pub. Co, 1985.

Cita MLA (9th ed.)

HARTMANN, William K. Astronomy the Cosmic Journey.-- Ed. 3. Wadsworth Pub. Co, 1985.