Easy Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 31: Two Easy (DiffLev 3-4) Hyperstoical Puzzles (numbers 141-142) 
 
-  Step-by-step instructions for solving  Puzzle 141, (48/144)   Diff: 3/991
 -  Step-by-step instructions for solving  Puzzle 142, (57/144)   Diff: 4/9991