BOSS spectrum of J1313−0019 (black) and best-fitting model (red). The elements or molecules associated with the most prominent lines are identified. The continuum correction has been carried out following the procedure described by Allende Prieto et al. (2014), namely dividing the spectral range in 20 segments and dividing the flux in each by its mean value. This algorithm is very robust to changes in the signal-to-noise ratio, and our own simulations show that has excellent performance.