  The problem of Gamma + Pi --> Pi + Pi is studied using the axial anomaly,
elastic unitarity, analyticity and crossing symmetry. Single variable
dispersion relation is assumed. Using elastic unitarity relation, an integral
equation equation for the lowest partial wave amplitude is obtained. The
solution for this integral equation is obtained by an iteration procedure
corresponding to that obtained from the vector meson dominance model but with
multiple scattering effects taken into account.
