  void print_point(std::ostream& out, const CGAL::Point_3<R>& p) {
    print_point_impl(out, Nef_3_internal::get_point(p) );
  }
  void print_point(std::ostream& out, const CGAL::Point_3<R>& p) {
    print_point_impl(out, Nef_3_internal::get_point(p) );
  }