Amplitudes of the observed light variations of RU Vir as shown in Fig. 8. For the JHKL filters the total amplitudes (m_max − m_min) of the data sample from Whitelock et al. (2006) are plotted with filled circles, together with the amplitude of the Fourier fit given by Whitelock et al. in their Table 3 plotted with open circles. For the BVRI filters only the first kind of amplitude is available and plotted with asterisks. In addition, the GCVS value for ΔV is shown with a filled square. The discrepancy in V is due to the limited sampling of the data obtained by Eggen (1975a).