Let X, Y be compact
Hausdorff spaces and let E, F be Banach spaces such that their duals are strictly
convex. We show that a linear map T : C(X,E) → C(Y,F) is an isometric
isomorphism if and only if there exists a homeomorphism ϕ : Y → X and a
continuous map λ from Y to the set of isometric isomorphisms from E onto F
(with the strong topology) such that Tf(y) = λ(y) ⋅ f(ϕ(y)) for all y ∈ Y ,
f ∈ C(X,E).