The 3800−8000 Å ptical spectra of the two main optical sources mentioned in this paper as possible optical counterparts of the X-ray source 1RXS J180431.1−273932 (see Fig. 1), that is, the most evident of the objects inside the X-ray error circle (left panel) and the bright one just outside it to the west (right panel). The former has a spectrum typical of a magnetic CV, while the latter shows the characteristics of a late-type giant star (see text). In both spectra, the telluric absorption bands are marked with the symbol  ⊕ .