103
Cumrun Vafa (Harvard University), interview with author, September 19, 2008.
104
Greene, interview with author, March 13, 2010.
105
Mark Gross (UCSD), interview with author, October 31, 2008.
106
Andreas Gathmann (University of Kaiserslautern), interview with author, August 25, 2008.
107
David Hilbert, “Mathematical Problems,” lecture, International Congress of Mathematicians, Paris, 1900, (html version prepared by David Joyce, Mathematics Department, Clark University, Worcester, Mass.).
