Left to right: WHAN diagram. The lines represent the division between gas ionised by AGN/star formation and “retired” galaxies (above and below the red line, respectively), the optimal transposition of the BPT-based division (Stasińska et al. 2006) between ionisation mechanisms driven by star formation and AGN (to the left and right of the black line, respectively), and of the Kewley et al. (2006) separation between Seyferts and LINERs (above and below the green line, respectively). The names of the galaxies are reported above each panel.