SIMBAD references

We present the results of the simultaneous spectral and polarimetric investigation of AB Aur - the Ae Herbig star from the "PCyg" subclass. About 150 high-resolution CCD spectra in the region of Hα and more than 100 UBVRI measurements of the linear polarization were obtained at the Crimean Astrophysical Observatory during two seasons in 1993 and 1994. Additional polarimetric observations in the B-band were carried out at the Special Astrophysical Observatory (Northern Caucasus). A strong variability of the Hα PCyg-type profile is analyzed on a timescale from hours to months. It is shown to be connected with circumstellar inhomogeneities moving in the envelope. The existence of a strong long-lived stream is supposed on the basis of joint spectral and polarimetric data in January 4-10, 1994.