Upper panel: comparison between observed photometry and flux-calibrated IUE and FUSE spectra (blue squares and lines) with the best-fitting model SED of AB 6 (red dotted line), which is the sum of the reddened SEDs of stars A, B, C, and D (black solid, green dotted, pink dashed, and cyan dot-dashed lines). Lower panels: comparison between normalized FUSE, IUE, and UVES spectra at ϕ ≈ 0.1 and the best-fitting normalized spectrum of AB 6, comprising the weighted models of stars A, B, C, and D. Line styles are as in the upper panel.