Difficult Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 23: Two Difficult (DiffLev 10-12) Demonstrably Puzzles (numbers 125-126) 
 
-  Step-by-step instructions for solving  Puzzle 125, (85/144)   Diff: 10/95.6997.9994
 -  Step-by-step instructions for solving  Puzzle 126, (86/144)   Diff: 12/9633.3999.9761