Gravitational models with non-local scalar fields
  A general class of f(R) gravity models with minimally coupling a nonlocal
scalar field is considered. The Ostrogradski representation for nonlocal
gravitational models with a quadratic potential and the way of its localization
are proposed. We study the action with an arbitrary analytic function
$F(\Box)$, which has both simple and double roots. The way of localization
allows to find particular solutions of nonlocal equations of gravity.
