Difficult Sudoku Twelve Logic Puzzles (Vol 1)
Chapter 19: Two Difficult (DiffLev 11-12) Columnarized Puzzles (numbers 117-118)
- Step-by-step instructions for solving Puzzle 117, (84/144) Diff: 11/954.7999.9633
- Step-by-step instructions for solving Puzzle 118, (84/144) Diff: 12/9895.4357.9972