Variations on Advanced Sudoku Logic Puzzles (Vol 1) 
 Chapter 19: Four Tournament HyperSudoku-12 Puzzles (numbers 57-60) 
 
-  Step-by-step instructions for solving  Puzzle 57, (96/144)   Diff: 22/98.6321.1B42.3241.2458.8965
 -  Step-by-step instructions for solving  Puzzle 58, (97/144)   Diff: 26/41.1C21.4322.3331.1C43.2369.8697
 -  Step-by-step instructions for solving  Puzzle 59, (108/144)   Diff: 26/74.31B2.2431.3343.2324.8978.6445
 -  Step-by-step instructions for solving  Puzzle 60, (104/144)   Diff: 27/6A1.3221.1354.5332.2211.2346.9992