Blue Brain Train Sudoku Book, 9x9 Puzzles, 150 Pages, 5x8, Easy

Blue Brain Train Sudoku Book, 9x9 Puzzles, 150 Pages, 5x8, Very Easy

Purple Brain Train Sudoku Book, 9x9 Puzzles, 150 Pages, 5x8, Easy

Red Brain Train Sudoku Book, 9x9 Puzzles, 150 Pages, 5x8, Easy

Orange Brain Train Sudoku Book, 9x9 Puzzles, 150 Pages, 5x8, Easy