B is for Brainy Sudoku: 200 Large Print Easy to Hard Puzzles (A-Z Sudoku Book Series): Gruden, Lou, Plus, Puzzle Books: 9798985346923: Amazon.com: Books
Amazon.com: Puzzle Baron's Number Logic Puzzles: Over 300 Brain-Challenging Puzzles-From Easy to Hard: 9781465490131: Baron, Puzzle: Books
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Binary puzzle book for Adults: 400 Very Hard Puzzles Mixed Grids (Volume 26): Gurin, Alena: 9798722142894: Amazon.com: Books
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Large Print Gokigen Puzzle Book 3: 100 Hard Puzzles: Quinlan, Kenneth, Publishing, WMC: 9781540518408: Amazon.com: Books
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Hard Logic Puzzles & Brain Games for Adults: 500 Puzzles & 12 Puzzle Types (Sudoku, Fillomino, Battleships, Calcudoku, Binary Puzzle, Slitherlink, ... (Challenging Fun Brain Teasers Series): Alzamili, Dr. Khalid: 9789922636092: Amazon.com: Books
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