1. Allen, D.A. 1973, M.N.R.A.S., 161, 145.
2. Appenzeller, I. 1970a, Astr. Ap., 5, 355.
3. Appenzeller, I. 1970b, Astr. Ap., 9, 216.
4. Barlow, M.J. and Cohen, M. 1977, Ap. J., 213, 737.
5. Davis, R.J., Deutchman, W.A. and Haramundanis, K.L. 1973, Celescope Catalog of Ultraviolet Stellar Observations, Smithsonian Astrophysical Observatory, Washington