One-dimensional spectra of the seven confirmed members of XMMU J0338.8+0021, smoothed with a 7 pixel boxcar filter. For each spectrum, an identification label (ID) and the measured redshift is reported. For the brightest component of the BCG (ID:1-A), the same LRG spectrum template used in Fig. 3 is overlaid in blue for comparison. In red, the sky features in absorption (top) and emission (bottom) are shown. The position of the main spectral features, shifted according to the corresponding redshift values, are marked by the vertical dashed lines.