Difficult Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 17: Two Difficult (DiffLev 13-14) Ambidextrous Puzzles (numbers 113-114) 
 
-  Step-by-step instructions for solving  Puzzle 113, (90/144)   Diff: 13/9.9899.4459.5353
 -  Step-by-step instructions for solving  Puzzle 114, (93/144)   Diff: 14/98.6559.9755.7561