SIMBAD references

High signal-to-noise ratio spectra have been taken to detect a possible circumstellar shell around λ Boo stars. It is more and more assumed that circumstellar matter can be found around such stars. We have considered the CaII K, Hγ and CaI λ4427 lines. Two spectra of λ Boo stars (HD 16955 and HD 104965) show circumstellar shell features in the K-line. Such features could also be present in the spectrum of HD 220061 and we confirm the circumstellar shell recently found for 131 Tau by Bohlender & Walker (1994).