Large Print SUDOKU Puzzles: 100+ Easy to Hard Puzzles - Train your brain anywhere, anytime - Vol.2

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Large Print SUDOKU Puzzles Book: 100+ Easy to Hard Puzzles - Train your brain anywhere, anytime!

Tutorial #80 A difficult sudoku puzzle made easy

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Tutorial 58. Hard sudoku puzzle with lots of techniques.

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Tutorial #40 A must know technique. NOT a puzzle.

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Sudoku Puzzle Book Large Print Volume.1- Easy Medium And Hard Levels

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Sudoku Puzzle Book - Over 400 Puzzles: 4 difficulty levels: Easy, medium, hard and very hard.

Tutorial #50 Solving a hard puzzle from the beginning to the end