Cita APA (7a ed.)

Keene, C. (1981). The clue in the crossword cipher. Armada books.

Cita Chicago Style (17a ed.)

Keene, Carolyn. The Clue in the Crossword Cipher. New York: Armada books, 1981.

Cita MLA (9a ed.)

Keene, Carolyn. The Clue in the Crossword Cipher. Armada books, 1981.