SDSS spectrum of J1048+31 at z = 0.452 (in gold) compared to the composite template of xA QSOs created by Marziani et al. (in prep.). The template (in black) is extinguished according to the SMC extinction law by Prevot et al. (1984), with progressively increasing values of E(B − V). The value of E(B − V) for which the reddened template (in red) matches with the observed SDSS spectrum corresponds to our estimate of the internal reddening of the source. J1048+31 has the largest E(B − V) among our sources, i.e. E(B − V) = 0.2.