Let M be a compact space, and
X a complete sparable metric space. Let P(X) denote the probability measures on
X. Let λ be a probability measure on M. Define a function φλ from C(M,P(X)) to
P(X) by φλ(T)(f) =∫T(t)(f)dλ(t) for every T ∈ C(M,P(X)), f ∈ C(X). We show
that φλ is an open mapping.