1. A. F. Nilov, Preprint No. 63-95, ITEP (Institute of Theoretical and Experimental Physics, Moscow, 1995).
2. M. Yu. Bogolyubski et al., Preprint No. 86-219, IHEP (Institute for High Energy Physics, Protvino, 1986).
3. K. G. Boreskov, A. B. Kaidalov, V. I. Lisin, et al., Yad. Fiz. 15, 361 (1972) [Sov. J. Nucl. Phys. 15, 203 (1972)].
4. K. G. Boreskov, A. P. Gasparyan, A. B. Kaidalov, et al., Yad. Fiz. 15, 557 (1972) [Sov. J. Nucl. Phys. 15, 309 (1972)].
5. K. G. Boreskov, A. B. Kaidalov, and L. A. Ponomarev, Yad. Fiz. 17, 1285 (1973) [Sov. J. Nucl. Phys. 17, 669 (1973)].