Equivalence of Volterra processes

In this paper we study necessary and sufficient conditions for the equivalence of Volterra Gaussian processes. Though this topic has already been studied in the literature, we provide new proofs, precisions and new theorems. We also give some examples of equivalent Volterra processes all related to the extensively studied fractional Brownian motion. Finally, we give an extension to general Gaussian processes of a recent regularization theorem by P. Cheridito.