Left panel (a): H_β-region spectra observed at orbital phases ϕ = 0.243 (BJD 2,460,263.0198) and ϕ = 0.750 (BJD 2,460,260.9902). The signature of the tertiary companion, indicated by an arrow, is well defined between the two absorptions of the eclipsing pair AB. Right panels (b) and (c): BF profiles for the same phases as before obtained using the RaveSpan code. The solid black lines indicate the BF profiles, which exhibit triple peaks and are fitted with three rotational profile functions representing the primary (blue), secondary (green), and third (cyan) components. The gray lines correspond to the combination of these rotational profiles.