Finite homomorphisms on rings of continuous functions

This paper deals with finiteness properties of the homomorphism between the rings of continuous functions C(Y)→C(X) induced by a continuous map X→Y. in result says that, for X and Y compact Hausdorff spaces, the homomorphism C(Y)→C(X) is finite (i.e., C(X) is finitely generated as a C(Y)-module) if and only if the map X→Y is locally injective.