[C/Fe]–[Fe/H] trends where the carbon abundances are based on the mean abundance coming from the different C I lines. In the top plot, all C I lines are included in the calculation of the mean C abundance for each star; in the middle plot C I lines located close to strong telluric lines (red marked lines in Fig. 2) were excluded when calculating the mean C abundance for each star; and in the bottom plot, all C I lines located close to a telluric line (orange and red lines in Fig. 2 and orange and red points in Fig. 6) were excluded from the calculation of the mean C abundance for each star. In each plot, we also indicate the median [C/Fe] value and the dispersion in [C/Fe].