  We analyze GKZ(Gel'fand, Kapranov and Zelevinski) hypergeometric systems and
apply them to study the quantum cohomology rings of Calabi-Yau manifolds. We
will relate properties of the local solutions near the large radius limit to
the intersection rings of a toric variety and of a Calabi-Yau hypersurface.
(Talk presented at "Frontiers in Quantum Field Theory", Osaka, Japan, Dec.1995)
