Masaki Hoshiko

Hard Sudokus Collection Book #21

Extremely Hard Sudokus Puzzle Book #12

Extremely Hard Sudokus Puzzle Book #11

Hard Sudokus Collection Book #23

The Hardest Sudokos Ever Made #8

Anti-dementia Sudokus #12

Extremely Hard Sudokus Puzzle Book #3

Extremely Hard Sudokus Puzzle Book #21

Anti-dementia Sudokus #13

Hard Sudokus Collection Book #20

Sudoku Smarts #10

Extremely Hard Sudokus Puzzle Book #6

Extremely Hard Sudokus Puzzle Book #5

Extremely Hard Sudokus Puzzle Book #17

Sudoku Smarts #17

Extremely Hard Sudokus Puzzle Book #16

Sudoku Smarts #14

Anti-dementia Sudokus #11

Extremely Hard Sudokus Puzzle Book #2

Extremely Hard Sudokus Puzzle Book #22

Extremely Hard Sudokus Puzzle Book #10

Extremely Hard Sudokus Puzzle Book #8

Sudoku Smarts #15

Extremely Hard Sudokus Puzzle Book #7