- Sudoku Hard Book 16: 100 Sudoku for Adults - Large Print - Hard Difficulty - Solutions at the End - 8'' x 10''
- Sudoku Hard Book 11: 100 Sudoku for Adults - Large Print - Hard Difficulty - Solutions at the End - 8'' x 10''
- Sudoku Hard Book 20: 100 Sudoku for Adults - Large Print - Hard Difficulty - Solutions at the End - 8'' x 10''
- Sudoku Hard Book 4: 100 Sudoku for Adults - Large Print - Hard Difficulty - Solutions at the End - 8'' x 10''
- Sudoku Hard Book 29: 100 Sudoku for Adults - Large Print - Hard Difficulty - Solutions at the End - 8'' x 10''