Notes. “Class” denotes the Tholen taxonomical class, N and K denote the numbers of observations and lightcurves, respectively, and T_obs is the time span of the observations. For Lutetia and Bilkis, the uppermost numbers refer to the ground-based observations, the ones in the middle to the GDR2 observations, and the lowermost ones refer to the combined observations. For Proserpina, the second row describes an additional sparse ground-based lightcurve. For the references to the observations, see Tables A.1–A.3.