Easy Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 36: Two Easy (DiffLev 3-4) Musicography Puzzles (numbers 151-152) 
 
-  Step-by-step instructions for solving  Puzzle 151, (50/144)   Diff: 3/991
 -  Step-by-step instructions for solving  Puzzle 152, (70/144)   Diff: 4/9992