The Ultimate Logic Grid Puzzle Book for Adults: 100 Fun and Challenging Puzzles (Logic Puzzles – The Ultimate Collection) Unicorn Books
Sudoku: Over 200 Puzzles & Solutions, Easy to Hard Puzzles for Adults, Spiral-Bound (Brain Busters) Parragon Books
200 Stress-Relieving Sudoku Puzzles to Sharpen Your Mind: Presented by Maria Shriver, Patrick Schwarzenegger, and MOSH (Puzzle Books for Brain Health) Maria, MOSH, Patrick, Schwarzenegger, Shriver