Cita APA (7a ed.)

Blashfield, J. F. (2001). Carl Sagan: Astronomer. Ferguson Pub. Co.

Cita Chicago Style (17a ed.)

Blashfield, Jean F. Carl Sagan: Astronomer. Chicago, Ill.: Ferguson Pub. Co, 2001.

Cita MLA (9a ed.)

Blashfield, Jean F. Carl Sagan: Astronomer. Ferguson Pub. Co, 2001.