Tarifications stables dans les monopoles multiproduits avec marchés séparés

We provide some existence results of stable pricings for natural monopoly as defined in the theory of contestable markets. The main addings are based on the assumption of separated markets and the possibilities of entries. We borrow tools from cooperative game theory. Following the work of Bendali et al. (Revista de Matematicas Aplicadas, 2000), we make full use of parameterized cores of games with side payments to characterize subsidy free and sustainable pricings.