Variations on Advanced Sudoku Logic Puzzles (Vol 1) 
 Chapter 13: Two Tournament Sudoku-12up Puzzles (numbers 37-38) 
 
-  Step-by-step instructions for solving  Puzzle 37, (92/144)   Diff: 24/6112.3454.2234.8533.5642.4771
 -  Step-by-step instructions for solving  Puzzle 38, (94/144)   Diff: 27/766.6432.1234.1132.11A2.2343.5974