Peter Buyin
Sudoku Scientist Winners Series - Sudoku Puzzle Books Advanced Edition for the Expert - Puzzle Books for Friends and Family Fun - Sudoku Puzzle Book Volume 4- Sudoku Scientist Winners Series - Sudoku Puzzle Books for the More Experienced Hard Edition - Puzzle Books for Friends and Family Fun - Sudoku Puzzle Book Volume 3
- Sudoku Scientist Winners Series - Sudoku Puzzle Books Medium Edition for Beginners - Puzzle Books for Friends and Family Fun - Sudoku Puzzle Book Volume 2