1. For a review see: Ngô, C.: Prog. Part. Nucl. (in press)
2. For a review see: Siemsen, R.H.: Nucl. Phys. A400, 245c (1983)
3. For a review see: Leray, S., Granier, O., Ngô, C., Tomasi, E., Cerruti, C., L'Hénoret, P., Lucas, R., Mazur, C., Ribrag, M., Charvet, J.L., Humeau, C., Lochard, J.P., Morjean, M., Patin, Y., Guinet, D., Vagneron, L., Peghaire, A.: XXIII International Winter Meeting on Nuclear Physics, Bormio (1985) 608
4. Sikkeland, T.: Phys. Lett.27B, 277 (1968)
5. Cerruti, C.: Thèse de doctorat d'Etat, Lyon (1983)