Abstract
We use rudiments of the Seiberg-Witten gluing theory for trivial circle bundles over a Riemann surface to relate de Seiberg-Witten basic classes of two
4
-manifolds containing Riemann surfaces of the same genus and self-intersection zero with those of the
4
-manifold resulting as a connected sum along the surface. We study examples in which this is enough to describe completely the basic classes.