This paper studies whether a regulator needs to correct the route structure choice by carriers with market power in the presence of congestion externalities, in addition to correct their pricing. We account for passenger benefits from increased frequency, passenger connecting costs, airline...

In this paper, I examine duopoly with multi-services, where firms offer delivery prices and mill prices at the same time, and each consumer chooses one of them. In the equilibria, firms specialize in delivery services even if their transport costs are higher than consumers'. This result is...