Super Sudoku Quad Samurai: 80 Overlapping Sudoku Puzzles, 13 Sudoku Grids in Each Puzzle (Super Quad Samurai Sudoku Books)
Super Sudoku Quad Samurai and variations: 99 Overlapping Sudoku Puzzles, 13 Sudoku Grids in Each Puzzle (Super Quad Samurai Sudoku Books)
Super Sudoku Quad Samurai Puzzles: 75 Overlapping Sudoku Puzzles, 13 Sudoku Grids in Each Puzzle (Super Quad Samurai Sudoku Books)