“…For the de Rham cohomology, it is shown in [57] that (5) holds in the case of OT manifolds of type (s, 1). For the Morse-Novikov cohomology, it was shown in [12] that the isomorphism (6) holds for a special class of OT manifolds of type (s, 1), namely, those satisfying the Mostow condition. However, using the description of the Morse-Novikov cohomology of OT manifolds given in [53], Istrati and Otiman show that (6) holds for any OT manifold of type (s, 1), even if the Mostow condition does not hold.…”