Sudoku: Over 50 puzzles in a travel sized book

Hard Sudoku Puzzles: 50+ Puzzles in a handy A5 travel sized book

pocket Sudoku: Easy: ...Over 100 easy sudoku puzzles in a handy sized book

Pocket Sudoku: 70+ Easy to Hard Puzzles in a Travel Sized Book

Sudoku Over 100 Easy Level Puzzles For A Calm Mind: Pocket Sudoku:...