Cita APA (7a ed.)

Silverberg, R. (1999). The Alien Years (1. pbk print.). HarperPrism.

Cita Chicago Style (17a ed.)

Silverberg, Robert. The Alien Years. 1. pbk print. New York: HarperPrism, 1999.

Cita MLA (9a ed.)

Silverberg, Robert. The Alien Years. 1. pbk print. HarperPrism, 1999.