Picturing Pythagorean triples. A Brief Course. Grattan-Guinness, I. 1998. The Rainbow of Mathematics. Veljan, D. 2000.
Comments are welcome.
He is the author of The Mathematical Tourist, Islands of Truth, Newton's Clock, Fatal Defect, and The Jungles of Randomness. A Mathematical Space Odyssey by Ivars Peterson and Nancy Henderson. For children ages 10 and up.