Randal Schwartz (Schwartz, Randal)

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  Effective Perl Programming: Writing Better Programs With Perl
  by Randal L. Schwartz, Joseph N. Hall
  Softcover, Addison-Wesley, ISBN 0201419750 (0-201-41975-0)
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  Learning Perl Objects, References and Modules
  by Randal L. Schwartz, Tom Phoenix, Damian Conway
  Softcover, O'Reilly Media, Incorporated, ISBN 0596004788 (0-596-00478-8)
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  Programming Perl
  by Larry Wall, Randal L. Schwartz
  Softcover, O'Reilly Media, Incorporated, ISBN 0937175641 (0-937175-64-1)
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  via
  Randal Schwartz's Perls of Wisdom
  by Randal L. Schwartz
  Softcover, Apress L. P., ISBN 1590593235 (1-59059-323-5)