Number Sums: Relaxing Logic Challenges: Puzzles Using Row and Column Sums

Number Sums: Math Logic Challenges: Puzzles Using Row and Column Sums (Number Puzzles)

Kakuro Cross Sums Volume IV (Number Logic Puzzles, Band 4)

Kakuro Cross Sums Volume III (Number Logic Puzzles, Band 3)

Kakuro Cross Sums Volume II (Logic Puzzles for Planes, Band 6)