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2. P. Pirila andS. Pokorski:Phys. Lett.,43 B, 502 (1973);F. Hayot andA. Morel:Nucl. Phys.,68 B, 323 (1974).
3. S. Pokorski andL. Van Hove: CERN preprint TH 1772 (1973).
4. F. Hayot andA. Morel:Lett. Nuovo Cimento,7, 221 (1973);8, 71 (1973).
5. F. C. Winkelmann : presented at theIV International Conference on Experimental Meson Spectroscopy, Boston, 1974.