Observations of Rapid Radial Velocity Variations of Spectral Lines in Rapidly Oscillating Ap (roAp) Stars Landstreet, J. D. ; Kochukhov, O. ; Kupka, F. ; Ryabchikova, T. ; Weiss, W. W. Abstract Publication: Asteroseismology Across the HR Diagram Pub Date: May 2003 Bibcode: 2003aahd.conf..347L