Bounded quantifiers have interval models

We propose a sound model for an extension of the language Fun, proposed by L. Cardelli and P. Wegner as a formalization of the notion of inheritance in the context of higher order polymorphic functional 1anguages. The model is obtained by modifying the Interval Model proposed by R. Cartwright, in order to accommodate bounded quantifiers and to obtain a sound structure. Our extension of the language supports also a general recursion operator for functions (but not for types).