“…where the series (4.9) and (4.10) converge in H 2 0 and L 2 (0,1), respectively, uniformly in t. Following the method used in [8], we will prove that a n = b n = 0 for any n = 1,2,..., and thus (ỹ(t),ỹ t (t)) = (0,0). Indeed, (ỹ(0),ỹ t (0)) = (ỹ 0 ,z 0 ) being in H 4 0 × H 2 0 (see (4.2)), one can claim that…”