  This paper deals with Pareto solutions of a nonsmooth fractional
interval-valued multiobjective optimization. We first introduce four types of
Pareto solutions of the considered problem by considering the lower-upper
interval order relation and then apply some advanced tools of variational
analysis and generalized differentiation to establish necessary optimality
conditions for these solutions. Sufficient conditions for Pareto solutions of
such a problem are also provided by means of introducing the concepts of
(strictly) generalized convex functions defined in terms of the
limiting/Mordukhovich subdifferential of locally Lipschitzian functions.
Finally, a Mond--Weir type dual model is formulated, and weak, strong and
converse-like duality relations are examined.
