Challenging Sudoku Twelve Logic Puzzles (Vol 1)
Chapter 40: Two Challenging (DiffLev 20) Overstudying Puzzles (numbers 159-160)
- Step-by-step instructions for solving Puzzle 159, (95/144) Diff: 20/3234.3412.5234.4798.9982
- Step-by-step instructions for solving Puzzle 160, (99/144) Diff: 20/5334.3446.5522.3469.9974