Michael Phelps, Businessman: The World's Greatest Olympian Writes His Second Act
Michael Phelps retires: Olympian tells SI why it's time - Sports Illustrated
Michael Phelps Autograph From Live Event On Speedo PC+ Olympic 08 Hologram | eBay
Olympic volunteers walk past a giant poster of U.S. swimmer Michael Phelps near the National Aquatics Center Olympic swimming venue in Beijing August 2, 2008. REUTERS/Ceerwan Aziz (CHINA Stock Photo - Alamy