Integrated spectra of the sample galaxies, obtained by summing the spectra of all spaxels in which the stellar continuum could be fitted by a template (see Sect. 2.4). Spectra are plotted in logarithmic flux scale and were shifted vertically. Major tick-marks on the y axis are spaced 1 dex apart. Nuclear spectra do not exhibit significantly distinct features from the integrated spectra and are not shown.