Easy Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 39: Two Easy (DiffLev 3-4) Overmatching Puzzles (numbers 157-158) 
 
-  Step-by-step instructions for solving  Puzzle 157, (60/144)   Diff: 3/991
 -  Step-by-step instructions for solving  Puzzle 158, (66/144)   Diff: 4/9992