1. Anderson, Robert, Glenn Ellison, and Drew Fudenberg, "A Non-Tipping Theorem: Integer Constraints and Equilibria in Two-Sided Markets," in preparation, 2003.
2. Billingsley, Patrick, Probability and Measure (New York, NY: Wiley, 1995).
3. Geographic Concentration as a Dynamic Process
4. Ellison, Glenn, Drew Fudenberg, and Markus Mobius, "Competing Auctions," unpublished, Massachusetts Institute of Technology and Harvard University, 2002.