Cita APA (7th ed.)
Dudeney, H. E., & Gardner, M. (1967). 536 puzzles & curious problems. Scribner.
Cita Chicago (17th ed.)
Dudeney, Henry Ernest, i Martin Gardner. 536 Puzzles & Curious Problems. New York: Scribner, 1967.
Cita MLA (9th ed.)
Dudeney, Henry Ernest, i Martin Gardner. 536 Puzzles & Curious Problems. Scribner, 1967.
Atenció: Aquestes cites poden no estar 100% correctes.