1. Brechtmann, C., Heinrich, W.: Nucl. Instrum. Methods B29, 675 (1988)
2. Brechtmann, C., Heinrich, W.: Z. Phys. A ? Atomic Nuclei330, 407 (1988)
3. Karol, P.J.: Phys. Rev. C11, 1203 (1975)
4. Lindstrom, P.J., Greiner, D.E., Heckman, H.H., Cork, B., Bieser, F.S.: Proceedings of the 14th International Cosmic Ray Conference, p. 2315, Munich 1975
5. Olson, D.L., Berman, B.L., Greiner, D.E., Heckman, H.H., Lindstrom, P.J., Crawford, H.J.: Phys. Rev. C28, 1602 (1983)