Amplitude ratios, frequency spectrum and ranks, associated auto-correlation function, and meridional cross-sections of the reference mode (n,ℓ,m) = (9,4,1) and the 9 other most similar modes, for an inclination of i = 60°. In the first row, the left panel shows the amplitude ratios, the dashed line corresponding to the reference mode (we note that this line is hardly visible because it is mostly covered up by the solid lines from the other modes), the middle panel gives the frequencies, where a higher rank indicates a higher resemblance with the reference mode, 10 corresponding to the reference mode, and the right panel displays the auto-correlation function of the sub-spectrum of the selected frequencies. The second and third rows show the meridional cross-sections of the selected modes. Beneath each mode, the values of (n,ℓ,m) are indicated when the mode corresponds to an island mode. Otherwise, only the azimuthal order, m, is provided.