  We study the rigid limit of type IIB string theory, compactified on a K3
fibration, which, near its conifold limit, contains the Seiberg-Witten curve
for N=2 SU(2) Super-Yang-Mills with a massive hypermultiplet in the fundamental
representation. Instead of working with an ALE approximation, we treat the K3
fibration globally. The periods we get in this way, allow for an embedding of
the field theory into a supergravity model.
