Sudoku XV [SUXV-3-008P]
Similar Puzzle Books
1000 Math Logic Puzzles – Collection II
US, CA; UK, IE, DE, FR, BE, ES, IT, NL, PL, SE; JP, AU 
Puzzles in this book: Calcudoku, Sudoku XV, Vudoku, Mathrax, Sandwich Sudoku, Killer Sudoku, Terra X, Little Unique Killer Sudoku, Frame Sudoku, and Sum Skyscrapers.
