1. Honora, L., Bregola, M., Ramusino Cott, P., and Martellini, M. (1988a).Physics Letters,205B, 53.
2. Honora, L., Rinaldo, M., Russo, J., and Wu, K. (1988b).Physics Letters,208B, 440.
3. Chang, D., and Kumar, A. (1987).Physics Letters,193B, 181.
4. Dai, Y. B., Huang, C. S., and Zhao, Z. Y. (1990).Physics Letters,236, 262.
5. Eguchi, T., and Ooguri, H. (1987).Nuclear Physics,240B, 308.