\begin{thebibliography}{599}

\bibitem{CS66} Ching R., Schaerf C., Phys. Rev. {\bf 141} 1320 (1966).

\bibitem{BGIJT74} Barashenkov V. S., Gerghi F. G., Iljinov A. S., {\it et al.},
Nucl Phys. {\bf A231} 462 (1974).

\bibitem{BSY78} Bauer T. H., Spital R. D., Yennie D. R., Rev. Mod. Phys. {\bf
50} 261 (1978).

\bibitem{PRW95} Piller G., Ratzka W., Weise W., Z. Phys. {\bf A352} 427 (1995).

\bibitem{ERR97} Engel R, Ranft J. and Roesler S., Phys. Rev.
 {\bf D55} 6957 (1997).
 
\end{thebibliography}