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  Discover Pat's Collection of Code PuzzlesTM
If you love Pat's "Coded Number Sudoku" then you will really love his collection of Code Letter and Code Number puzzles. Each book is jam packed with new puzzles exclusively from Pat. Whether you like word puzzles, number puzzles or trivia quizzes Pat has brought his unique style of puzzle play to each. His patent-pending Coded Puzzle system is sure to entertain for hours on end.