Upper panel: continuum correction using eight iterations for the inversion of HD 97230. Only iterations 1 and 8 are shown for the sake of clarity, The initial observation is indicated with a solid line, the 1st iteration is indicated with dash-dotted line, the 8th iteration is indicated with double dash-dotted line, and the final best-fit synthetic spectrum is indicated with a dashed line. Lower panel: ratios between the re-normalized spectrum of the observation and the first neighbour best-fit synthetic spectrum for iterations 1, 2, and 8.