1. E. Abate, G. Bellini, E. Fiorini, and S. Ratti, Nuovo Cimento
22, 1206 (1961).
2. G. Andersson, P. Dougan, and W. Steifler, Z. Physik
A272263 (1975).
3. H. Araseki and T. Fujita, Nucl. Phys. A399434 (1983).
4. J, Aichelin, J. HüfnerPhys. Lett. B, in press.
5. J, Aichelin, J. Hüfner, and R. Ibarra, Phys. Rev. C., submitted.