1. EMC Collab., J. Ashman et al.: Phys. Lett. B 206 (1988) 364
2. See for example: H. Rollnik: Proceedings of the ninth International Symposium on High-Energy Spin-Physics, Bonn, 1990, p. 183, K.H. Althoff, W. Meyer. (eds.) Berlin, Heidelberg, New York: Springer 1991, and the references cited therein
3. See for example: K. Rith: Proceedings of the ninth International Symposium on High-Energy Spin-Physics, Bonn, 1990, p. 198 K.H. Althoff, W. Meyer. (eds.) Berlin, Heidelberg, New York: Springer (1991), and the references cited therein
4. L.L. Frankfort et al.: Phys. Lett. 230B (1989) 141
5. Liang Zuo-tang, Meng Ta-chung: Z. Phys. A 344 (1992) 171: C. Boros, Liang Zuo-tang, Meng Ta-chung: Preprint FUB/HEP 92-3 (1992)