1. A. Araujo, and, H. Moreira, Adverse selection problems without the single crossing property, mimeo, Universidade Federal Fluminense, Brasil, 1998.
2. Multidimensional nonlinear pricing;Armstrong;Econometrica,1996
3. Nonlinear pricing and price cap regulation;Armstrong;J. Public Econ.,1994
4. M. Bagnoli, and, T. Bergstrom, Log-concave probability and its applications, mimeo, University of Michigan, 1989.
5. Regulating a monopoly with unknown costs;Baron;Econometrica,1982