“…In passing, we note that our formulation particularized for transversely isotropic materials and isotropic materials coincides with the ones given in [62] and [84], respectively. In particular, for instance, the matrices N 1 , N 2 and K in (3.21) particularized for isotropic materials coincide, respectively, with the matrices N 1 , N 2 and N 3 + XI, where X = ρc 2 , given by (2.9) and (2.10) in [84].…”