Variations on Intermediate Sudoku Logic Puzzles (Vol 1) 
 Chapter 13: Four Easiest Sudoku-7B-2V Puzzles (numbers 65-68) 
 
-  Step-by-step instructions for solving  Puzzle 65, (17/49)   Diff: 2/91
 -  Step-by-step instructions for solving  Puzzle 66, (17/49)   Diff: 2/91
 -  Step-by-step instructions for solving  Puzzle 67, (17/49)   Diff: 2/91
 -  Step-by-step instructions for solving  Puzzle 68, (17/49)   Diff: 2/91