Abundances of Zr in the three RGB stars common to the GIRAFFE (this study) and UVES samples (Thygesen et al. 2014) determined by us using Zr I and Zr II lines in the GIRAFFE and UVES spectra (Table B.3 and B.4, Sect. B.2.4) and plotted against the effective temperature (top) and [Na/Fe] ratio (bottom). The mean abundances obtained using Zr I lines in the GIRAFFE and UVES spectra are shown by solid red and green triangles, respectively, while the mean abundances obtained from Zr II lines are plotted as green circles; and abundances determined from individual Zr II lines in the UVES spectra are shown as hollow circles.