Publishing, LAM Sudoku Book for Adults with 4 Levels of Difficulty: 400 Puzzles With Solutions Easy to Expert Grids Boost Brainpower, Focus & Stress Relief 6x9 Inch Size (Travel Sized Sudoku Challenge)

Smith, Puzzle Christmas Sudoku Book for Adults and Seniors Difficulty mixed 800 Puzzles & Solutions, mixed Level: The Perfect Gift for Puzzle Lovers

Publishing, LAM Medium Sudoku Puzzle Book For Adults: 400 Medium Level Sudoku Grids for Adults Boost Brainpower, Sharpen Focus & Enjoy Stress Relief 6x9 Inch ... Logic Fun (Travel Sized Sudoku Challenge)

Publishing, LAM Hard Sudoku Puzzle Book: For Adults and Seniors 400 Grids for Serious Brain Training & Relaxation 6x9 Inch Format, Solutions Included (Travel Sized Sudoku Challenge)

SIVA GANESH, MUGADA Huge Book of Large Print Sudoku Puzzles: for Adults, Teens, & Seniors, More Than 500 Puzzles & solutions, with 4 Levels of Difficulty Easy, Medium, Hard, & Expert

SIVA GANESH, MUGADA Huge Book of Large Print Sudoku Puzzles: for Adults, Teens, & Seniors, More Than 500 Puzzles & solutions, with 4 Levels of Difficulty Easy, Medium, Hard, & Expert

Horshkova, Anastasiia Sudoku puzzel book: Sudoku Book for Adults and Seniors with 4 Levels of Difficulty: 544 Puzzles & Solutions, Easy to Expert