Available RVs of β Lyr B. The first three datasets are RVs measured on photographic spectra of moderate dispersion: green open circles denote the RVs measured by Petrie & Pearce (1961), the red open triangles come from Abt et al. (1962), and the black boxes are RVs from Abt & Levy (1976). The filled blue diamonds are the RVs measured on Ondřejov electronic spectra with PYTERPOL. The rms errors, available only for Abt & Levy (1976) and new RVs are also shown. We note that the most deviant RV of −45 km s⁻¹ is based on a single line and comes probably from an underexposed spectrum.