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Godwin, Grover Maurice. Hunting Serial Predators: A Multivariate Classification Approach to Profiling Violent Behavior. Boca Raton, FL: CRC Press, 2000.
Godwin, Grover Mauriece, ed. Criminal Psychology and Forensic Technology: A Collaborative Approach to Effective Profiling. Boca Raton, FL: CRC Press, 2000.
Graysmith, Robert. Zodiac. New York: Berkley, 1976.
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Jarvis, Charles. "Academic Sleuth Made Startling Prediction," The News and Observer, March 20, 1997.
Kalfrin, Valerie, "The Makings of a Suspected Killer," APBNews, July 13, 1999.
Rossmo, D. K. "Geographic Profiling," in Offender Profiling: Theory, Practice and Research, edited by Janet L. Jackson and Debra Bekerian. New York: Wiley, 1999.
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Turvey, Brent. Criminal Profiling. San Diego, CA: Academic Press, 1999.