  In this work, we consider an inverse problem of determining a source term for
a structural acoustic partial differentia equation (PDE) model, comprised of a
two or three-dimensional interior acoustic wave equation coupled to a Kirchoff
plate equation, with the coupling being accomplished across a boundary
interface. For this PDE system, we obtain the uniqueness and stability estimate
for the source term from a single measurement of boundary values of the
"structure". The proof of uniqueness is based on Carleman estimate. Then, by
means of an observability inequality and a compactness/uniqueness argument, we
can get the stability result. Finally, an operator theoretic approach gives us
the regularity needed for the initial conditions in order to get the desired
stability estimate.
