Smith, G. h. (2001). Celsum's challenge: A skeptic's guide... White stone.
Cita Chicago (17th ed.)Smith, Gerald h. Celsum's Challenge: A Skeptic's Guide... anchorage: White stone, 2001.
Cita MLA (9th ed.)Smith, Gerald h. Celsum's Challenge: A Skeptic's Guide... White stone, 2001.
Atenció: Aquestes cites poden no estar 100% correctes.