Wow! Cutting edge journalism and science too! Here are the attributions from the snopes.com article on the same topic. Some of the articles pre-date the www.
Abrahamson, Alan. € "Prevalence of Drug-Tainted Money Voids Case."
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Los Angeles Times. € 13 November 1994 € (p. B1).
€ € Price, Debbie. € "Use of Drug-Sniffing Dogs Challenged."
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The Washington Post. € 6 May 1990 € (p. D1).
€ € Ritter, Jim. € "4 out of 5 Dollar Bills Show Traces of Cocaine."
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Chicago Sun-Times. € 26 March 1997 € (p. S10).
€ € Sones, Bill and Rich Sones. € "Most U.S. Bills Contaminated with Traces of Cocaine."
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Chicago Sun-Times. € 19 October 1997 € (p. 47).
€ € Wagner, Michael. € "Why There's Cocaine on Your Money."
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Sacramento Bee. €16 November 1994 € (p. A1).
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Knight-Ridder News Service. € "Cocaine Found on Money in Miami."
€ € The [Bergen County] Record. € 17 January 1985 € (p. D31).