Books in the Hard Sudoku series

Hard Sudoku Puzzles Volume 4 200 Challenging Puzzles Activity GiantsThe fourth in a new series: hard puzzles for serious sudoku solvers.Do you have what it takes? These 200 challenging sudoku puzzles will keep your mind sharp!Features: - 200 hard puzzles- Big grids for easy solving

Hard Sudoku Puzzles Volume 3 200 Challenging Puzzles Activity GiantsThe third in a new series: hard puzzles for serious sudoku solvers.Do you have what it takes? These 200 challenging sudoku puzzles will keep your mind sharp!Features: - 200 hard puzzles- Big grids for easy solving

Hard Sudoku Puzzles Volume 1 200 Challenging Puzzles Activity GiantsThe first in a new series: hard puzzles for serious sudoku solvers.Do you have what it takes? These 200 challenging sudoku puzzles will keep your mind sharp!Features: - 200 hard puzzles- Big grids for easy solving

Hard Sudoku Puzzles Volume 2 200 Challenging Puzzles Activity GiantsThe second in a new series: hard puzzles for serious sudoku solvers.Do you have what it takes? These 200 challenging sudoku puzzles will keep your mind sharp!Features: - 200 hard puzzles- Big grids for easy solving