Medium Sudoku Twelve Logic Puzzles (Vol 1)
Chapter 40: Two Medium (DiffLev 6-7) Overstudying Puzzles (numbers 159-160)
- Step-by-step instructions for solving Puzzle 159, (79/144) Diff: 6/99.9996
- Step-by-step instructions for solving Puzzle 160, (82/144) Diff: 7/999.9922