1. K.Rykaczewski et al., Proc. 5th Int. Conf. on Nuclei Far from Stability, Rosseau Lake (1987), ed.I.S.Towner, p.656
2. R. Barden et al., Z.Phys. A329, 319 (1988)
3. E.Roeckl, Contribution to this Workshop
4. J. van Maldeghem, K. Heyde, J.Sau, Phys.Rev. C32, 1067 (1985)
5. G.A.Leander et al., Phys.Rev. C30, 416 (1984)