Challenging Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 7: Twelve Challenging (DiffLev 15-17) HyperSudoku-12 Puzzles (numbers 49-60) 
 
-  Step-by-step instructions for solving  Puzzle 49, (85/144)   Diff: 15/975.2342.4765.9552
 -  Step-by-step instructions for solving  Puzzle 50, (94/144)   Diff: 16/9858.7136.6644.9654
 -  Step-by-step instructions for solving  Puzzle 51, (95/144)   Diff: 16/9677.6437.5564.6782
 -  Step-by-step instructions for solving  Puzzle 52, (96/144)   Diff: 16/9952.A356.8559.8494
 -  Step-by-step instructions for solving  Puzzle 53, (102/144)   Diff: 16/5443.5656.8898.9961
 -  Step-by-step instructions for solving  Puzzle 54, (87/144)   Diff: 17/9.5975.2233.2134.9971
 -  Step-by-step instructions for solving  Puzzle 55, (90/144)   Diff: 17/9.9464.332C.4236.7972
 -  Step-by-step instructions for solving  Puzzle 56, (91/144)   Diff: 17/9.4111.4365.4349.9992
 -  Step-by-step instructions for solving  Puzzle 57, (97/144)   Diff: 17/7.6543.2123.4999.9963
 -  Step-by-step instructions for solving  Puzzle 58, (99/144)   Diff: 17/9.6354.5254.6457.9982
 -  Step-by-step instructions for solving  Puzzle 59, (100/144)   Diff: 17/9.5679.4427.6956.8562
 -  Step-by-step instructions for solving  Puzzle 60, (107/144)   Diff: 17/6.3244.3348.6999.8897