[N II] BPT diagrams for individual galaxies, with SF-like (in blue), composite (in green) and AGN-like (in red) characteristics. Black curves, solid and dashed, represent the borders between the different regions, as defined in Kauffmann et al. (2003) and Kewley et al. (2001). The mean error in both axis is represented as a cross in the bottom right corner area of each diagram. Only fibres with a S/N > 3 in all lines used are shown. Outlined points represent DIG fibres. The BPT diagrams for the rest of the sample can be found in Appendix C.