10 books • 4 series
Tony Blair
The Penguin Book of Curious and Interesting Mathematics (Penguin mathematics)
You are a Mathematician
The Guinness Book of Brain-teasers
The Penguin Book of Curious and Interesting Puzzles (Penguin science)
Problem Solving for National Curriculum Mathematics
Mathematics Through Problem-solving (Problem Solving for National Curriculum Mathematics)
Can You Solve These?
Solve it! (The Dragon Books)
Recreations in Logic