1. Bar-Nun, A., Kleinfeld, J. and Kochavi, E.: 1988, Phys. Rev. B. 38, 7749–7754.
2. Bar-Nun, A. and Kleinfeld, I.: 1989, Icarus 80, 243–253.
3. Bradley, J. P., Sandford, S. A. and Walker, R. M.: 1988, in: J. F. Kerridge and M. S. Matthews, eds)., Meteorites and the Early Solar System, University of Arizona Press, Tucson, 861–898.
4. Broadfoot, A. L. et al.: 1989, Science 246, 1459–1465.
5. Conrath, B., Gautier, D. and Owen, T.: 1993, Icarus submitted.