“…Unfortunately, in Section 7 of [16], the authors did not take into consideration that for t ≤ t 0 , φ t (W α,G ) is not necessarily controlled by the cones defined by (3.2), and thus could be an inadmissible manifold. Such an issue can be easily fixed, in the present context, by introducing a dynamical norm (similarly to [8]) as done below. This however is not suitable for studying perturbation theory, to this end a more radical change of the Banach space is required [17].…”