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H.A. Abt (Kitt Peak National Observatory)
Stellar line widths yield values of V sin i, but the equatorial rotational velocities, V, cannot be determined for individual stars without knowledge of their inclinations, i, relative to the lines of sight. For large numbers of stars we generally assume random orientations, but is that valid? For eclipsing binaries i is known. For spotted stars we have independent information about rotational periods. We considered data for 140 Ap stars for which Catalano and Renson compiled rotational periods from the literature and we used the line widths by Abt and Morrell. We found that rotational axes are oriented randomly. Also they show no dependence upon galactic latitude or longitude.