Challenging Sudoku-by5 Logic Puzzles (Vol 1) 
 Chapter 8: Twenty Challenging (DiffLev 20) Sudoku-by5 Puzzles (numbers 81-100) 
 
-  Step-by-step instructions for solving  Puzzle 81, (233/369)   Diff: 20/9999.9976.762C.2223.7756
 -  Step-by-step instructions for solving  Puzzle 82, (252/369)   Diff: 20/9999.9999.9983.552B.2444
 -  Step-by-step instructions for solving  Puzzle 83, (252/369)   Diff: 20/9999.9978.7989.9997.9994
 -  Step-by-step instructions for solving  Puzzle 84, (253/369)   Diff: 20/9999.9999.9996.522D.5654
 -  Step-by-step instructions for solving  Puzzle 85, (254/369)   Diff: 20/9999.9998.9899.9999.9566
 -  Step-by-step instructions for solving  Puzzle 86, (258/369)   Diff: 20/9999.9999.9999.7476.8343
 -  Step-by-step instructions for solving  Puzzle 87, (259/369)   Diff: 20/9999.9997.9998.9999.9532
 -  Step-by-step instructions for solving  Puzzle 88, (261/369)   Diff: 20/9999.9999.9869.9999.7544
 -  Step-by-step instructions for solving  Puzzle 89, (261/369)   Diff: 20/9999.6785.8999.9999.9552
 -  Step-by-step instructions for solving  Puzzle 90, (261/369)   Diff: 20/9998.9998.9899.9999.9994
 -  Step-by-step instructions for solving  Puzzle 91, (262/369)   Diff: 20/9999.9999.9999.8B63.5544
 -  Step-by-step instructions for solving  Puzzle 92, (262/369)   Diff: 20/9999.9999.9998.5379.9341
 -  Step-by-step instructions for solving  Puzzle 93, (265/369)   Diff: 20/9999.9999.9999.9787.9972
 -  Step-by-step instructions for solving  Puzzle 94, (266/369)   Diff: 20/9999.6999.9999.9988.9947
 -  Step-by-step instructions for solving  Puzzle 95, (267/369)   Diff: 20/9999.9999.9999.9999.9832
 -  Step-by-step instructions for solving  Puzzle 96, (267/369)   Diff: 20/9999.9999.9999.9996.7994
 -  Step-by-step instructions for solving  Puzzle 97, (268/369)   Diff: 20/9999.9999.9999.9967.9992
 -  Step-by-step instructions for solving  Puzzle 98, (268/369)   Diff: 20/9976.4459.9999.9999.9999
 -  Step-by-step instructions for solving  Puzzle 99, (270/369)   Diff: 20/9999.9999.9999.9999.9991
 -  Step-by-step instructions for solving  Puzzle 100, (272/369)   Diff: 20/9999.9797.9999.9999.9974