Amazon.com: Stay Calm And Solve Sudoku #21: Greatest Sudoku Collection With 300 Medium Difficulty Sudoku Puzzles To Challenge Your Brains: 9781690497202: Hoshiko, Masaki: Books
Amazon.com: Bedtime Sudokus #21: Improve Your Sudoku Game With This Well Crafted Sudoku Puzzle Book (Medium To Advance Difficulty): 9781690497707: Hoshiko, Masaki: Books