Difficult Sudoku Twelve Logic Puzzles (Vol 1)
Chapter 16: Two Difficult (DiffLev 12-13) tpsmith-serious Puzzles (numbers 111-112)
- Step-by-step instructions for solving Puzzle 111, (93/144) Diff: 12/9956.3467.8993
- Step-by-step instructions for solving Puzzle 112, (85/144) Diff: 13/9.9793.5477.6593