Cita APA (7th ed.)

Sitchin, Z. (1976). The 12th planet. Avon Books.

Cita Chicago (17th ed.)

Sitchin, Zecharia. The 12th Planet. New York, New York: Avon Books, 1976.

Cita MLA (9th ed.)

Sitchin, Zecharia. The 12th Planet. Avon Books, 1976.