Top a) spectra of a possible O star (SIMBAD identifier [S87b] IRS 38), a probable O star ([S87b] IRS 42), and two UVES/POP spectra of known O stars. The lower two spectra were slightly smoothed to improve their visibility. Dashed vertical lines indicate Hα and He I 6678 Å, as above, plus the He II lines at 6527 and 6684 Å, typical of O stars. Bottom b) example spectra of new candidate Herbig Ae/Be stars discovered in this work.