Sudoku Puzzle Book for Adults: 100 Sudoku Level 4 9×9 (Difficult Sudoku Books for Adults) – hundred all-new extra-challenging Sudoku puzzles – volume 2
Sudoku level 4 is a collection of hard sudoku problems. There are 100 classical Sudoku (9×9) puzzles and their solutions in this book. This sudoku is for experienced users only!!! Fill In Puzzles Book Killer Sudoku Logic 100 level 4 / evil Puzzles For Adults, Seniors And Killer Sudoku Brain Games for Adults. This book with hundreds of hours of fun inside makes a great gift! Sudoku helps keep your brain healthy and functioning well. Challenge yourself to finish all the puzzles without cheating! hundred all-new extra-challenging Sudoku puzzles.