An Imaginary Tale: The Story of √-1 (Princeton Science Library)
e: The Story of a Number (Princeton Science Library)
—
Dr. Euler's Fabulous Formula: Cures Many Mathematical Ills
A History of Pi
The Golden Ratio: The Story of PHI, the World's Most Astonishing Number
Prime Obsession: Bernhard Riemann and the Greatest Unsolved Problem in Mathematics