1. Boyer, R.: 1978,Astron. Astrophys. 69, 213.
2. Cassatella, A., Ponz, D., and Selvelli, P. L.: 1981IUE Newsletters No. 10.
3. Dieke, G. H. and Crosswhite, H. M.: 1962,J. Quant. Spectrosc. Radiat. Transfer. 2, 97.
4. Faraggiana, R. and Hack, M.: 1976,Astrophys. J. Suppl. Ser,32, 501.
5. Fern�ndez-Figueroa, M. J., Rego, M. and Cornide, M.: 1980,Astron. Astrophys. 82, 221.