Competitive Product Lines with Quality Constraints
Udo Schmidt Mohr, Miguel Villas-Boas
Quantitative Marketing And Economics, vol. 6, 2008, p. 1-16.

Oligopoly with Asymmetric Information: Differentiation in Credit Markets
Miguel Villas-Boas, Udo Schmidt Mohr
Rand Journal of Economics, vol. 30, 1999, p. 375-396.