Top: average spectra of the different subclasses of M-type dwarf identified in our spectral sample. Middle: average spectra of the most common types of C-type giants identified in our sample. Bottom: average spectrum of the genuine dK7 sources in our sample and the average spectrum of those sources classified as K-type dwarf stars by the matching program but which were reclassified as early C-type stars (bold line) following a visual inspection. The C3.2 average spectrum is plotted again for comparison.