  A non-local gravity model, which includes a function $f(\Box^{-1} R)$, where
$\Box$ is the d'Alembert operator, is considered. For the model with an
exponential $f(\Box^{-1} R)$ de Sitter solutions are explored, without any
restrictions on the parameters. Using Hubble-normalized variables, the
stability of the de Sitter solutions is investigated, with respect to
perturbations in the Bianchi I metric, in the case of zero cosmological
constant, and sufficient conditions for stability are obtained.
