Metric Estimates for the Calculus of Multimappings

The present paper completes previous results of Penot and Jourani dealing with continuity properties of multimappings obtained via intersections or inverse images. A key role is played by estimates of metric regularity type. These estimates have consequences on the calculus of generalized derivatives and on the computation of normal cones. The considered multimappings are not supposed to have convex values, but when this property holds, simple qualification conditions ensure these estimates.