1. Bernasconi, P.N., Keller, C.U., Povel, H.P., Stenflo, J.O.: 1995, Astron. Astrophys., in press
2. Bernasconi, P.N., Aebersold, F., Egger, U., Keller, C.U., Povel, H.P., Solanki, S.K., Steiner, P., Stenflo, J.O.: Astron. Astrophys., in preparation
3. Emonet, T.: 1992, Diploma Thesis, ETH, Zürich
4. Keller, C.U., Bernasconi, P.N., Egger, U., Povel, H.P., Steiner, P., Stenflo, J.O.: 1995, LEST Technical Report No. 59
5. Maltby, P., Avrett, E.H., Carlsson, M., Kjeldseth-Moe, O., Kurucz, R.L., Loeser, R.: 1986, Astrophys. J. 306, 284