  In this work we analyze the generalization of Duffin-Kemmer-Petiau equation
to the case of Riemannian space-times and show that the usual results for
Klein-Gordon and Proca equations in Riemannian space-times can be fully
recovered when one selects, respectively, the spin 0 and 1 sectors of
Duffin-Kemmer-Petiau theory.
