Bolometric luminosity as a function of time for SN 2013L together with SN 2010jl. The dashed lines represent the luminosity predicted for a model with the velocity dependence from Eq. (9) and mass-loss rates Ṁ = 1.7 × 10⁻² M_⊙ yr⁻¹ and Ṁ = 9 × 10⁻² M_⊙ yr⁻¹, respectively. For SN 2013L the blue dots refer to luminosities derived from optical spectral fits, while the diamonds refer to NIR fits.