23 SBCRs in the literature plotted as a function of the V − K colour (over their validity domain), and comparatively to the Kervella et al. (2004a) relation in ΔF_V on the top right corner, between 0.5 and 3.0 mag, which is taken as a reference (for clarity). We note, however, that the Kervella et al. (2004a) relation is in principle valid only over the −0.85 to 4.10 V − K range. The references for these SCBRs are as follows: Fouque & Gieren (1997), van Belle (1999), Nordgren et al. (2002), Kervella et al. (2004a,b), di Benedetto (1993, 1998, 2005), Groenewegen (2004), Boyajian et al. (2014), Graczyk et al. (2017), Bonneau et al. (2006), and Challouf et al. (2014).