Dr. X (Dr X.)

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  via
  The Complete Hacker's Handbook: Everything You Need to Know About Hacking in the Age of the Web
  by K. Dr
  Softcover, Andrews McMeel Pub, ISBN 1858684064 (1-85868-406-4)
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  How to Stop the IRS ... and Solve the Deficit Problem
  by Dr X.
  Hardcover, Vista Research Corporation, ISBN 0944848001 (0-944848-00-1)