1. H. A. Zook and J.-C. Liou, SN3, NASA Johnson Space Center, Houston, TX 77058, USA.
2. E. Grün, M. Baguhl, G. Linkert, Max-Planck-Institut für Kernphysik, Postfach 103980, 69029 Heidelberg, Germany.
3. D. P. Hamilton, Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA.
4. R. Forsyth, The Blackett Laboratory, Imperial College, London SW7 2BZ, UK.
5. J. L. Phillips, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.