1. Schmidt-Kaler, Th. in: Landolt-Börnstein, NS, Vol. VI/1 (1965) p. 311 and references therein.
2. Slettebak, A. (ed.): Stellar Rotation, Proc. Int. Astron. Union Colloq. of Columbus, Reidel, Dordrecht (1970).
3. Tassoul, J.-L.: The Theory of Rotating Stars, Princeton (1978).
4. Slettebak, A., Collins, G.W., Boyce, P.B., White, N.M., Parkinson, T.D.: Astrophys. J. Suppl. 29 (1975) 137.
5. Hardorp, J., Strittmatter, P.A.: Astrophys. J. 153 (1968) 465; Hardorp, J., Scholz, M.: Astron. Astrophys. 13 (1971) 353.