Map of the 24 bona fide QSOs (red squares) with prominent emission lines and 1 BL Lac object (red dot) known from the literature before Gaia DR3 (Gaia Collaboration 2023b). The confirmed QSOs from our target list are also shown: 3 Spitzer-selected (cyan), 2 selected from optical colors and UV excess (yellow), and 18 selected by other means (see Table A.1; black). All objects are located within the µ_B = 26^m/□″ isophote (black solid line). The µ_B=25^m/□″ isophote (dotted line), the approximate boundaries of the Spitzer PSC catalog (dashed line) and the footprints of LGGS (red) and PHAT (blue) catalogs are also plotted.