Red Brain Train Sudoku Book, 9x9 Puzzles, 300 Pages, 5x8, Medium

Red Brain Train Sudoku Book, 9x9 Puzzles, 300 Pages, 5x8, Evil

Yellow Brain Train Sudoku Book, 9x9 Puzzles, 300 Pages, 5x8, Medium

Green Brain Train Sudoku Book, 9x9 Puzzles, 300 Pages, 5x8, Medium

Pink Brain Train Sudoku Book, 9x9 Puzzles, 300 Pages, 5x8, Medium