Cita APA (7a ed.)

Sagan, F., & Ash, I. (1961). Those without shadows. Penguin.

Cita Chicago Style (17a ed.)

Sagan, Françoise, y Irene Ash. Those Without Shadows. Harmondsworth: Penguin, 1961.

Cita MLA (9a ed.)

Sagan, Françoise, y Irene Ash. Those Without Shadows. Penguin, 1961.