Histogram of l.o.s. velocity measurements from the analyzed datasets. Left: comparing the velocities from the P91-FORS2 dataset with those from literature, i.e. Fraternali et al. (2009) and Gregory et al. (2019). Right: same comparison using instead the velocity measurements from our reduction of the P69-FORS2 and FLAMES datasets. Note that, in the left panel, the peaks of the histograms fall at different velocities, while in the right panel, where the datasets shown were analyzed homogeneously, these differences are absent.