Cita APA (7a ed.)

Kaufmann, W. J. (1987). Discovering the universe. W. H. Freeman.

Cita Chicago Style (17a ed.)

Kaufmann, William J. Discovering the Universe. New York: W. H. Freeman, 1987.

Cita MLA (8a ed.)

Kaufmann, William J. Discovering the Universe. W. H. Freeman, 1987.