1. M. P. Golombek, R. A. Cook, W. M. Folkner, A. F. C. Haldemann, P. H. Kallemeyn, R. M. Manning, T. J. Parker, J. T. Schofield, R. M. Vaughan, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
2. T. Economou, University of Chicago, Enrico Fermi Institute, Chicago, IL 60637, USA.
3. J. M. Knudsen, Niels Bohr Institute, University of Copenhagen, Denmark.
4. H. J. Moore, U.S. Geological Survey, Scientist Emeritus, Astrogeology Team, Menlo Park, CA 94025, USA.
5. R. Rieder, Max Planck Insitute for Chemistry, Mainz, Germany.