“…The results were computed with 28, 56 and 112 elements, and compared with those from Ref. [6] with 50 elements for the TM case and 40 for the TE and [9], showing again very good accordance. The last example, that of a T-septate rectangular waveguide of dimensions a = 1.0 cm, b =0.45 cm, d =0.25 cm, W =0.125 cm, is the most demanding one ( Table 7).…”