Feature●Each measures 10 3/4" x 7 1/2" and contains 64 pages●Hard to find Sunday size 16 Grid Sudoku Puzzles, use numbers 1 through 16 instead of 1 through 9.●Volumes 87 and 88●Please see all pictures for samples of puzzles you will find inside.●Ready for a challenge? Each row, column, and diagonal must contain the numbers 1 to 16.Description These are the hard to find 16 grid sudoku puzzles Instead of just using the numbers 1-9, you use the numbers 1-16... Each book measures 10 3/4" x 7 1/2" and contains 64 pages each. Please see all pictures for sample of puzzles you will find inside.