"The Feynman Lectures on Physics (volume I; lecture 3: "The Relation of Physics to Other Sciences")". Book by Richard P. Feynman, Robert B. Leighton and Matthew Sands, 1964.
"FIVE QUESTIONS FOR . . . / Ben Bradlee and Sally Quinn / Journalism heroes turn focus to aging". Interview with Paul Wilner, www.sfgate.com. May 15, 2005.