1. Ya. B. Fainberg, in: Proceedings of the Seventh International Conference on Charged-Particle Accelerators [in Russian], Vol. 2, Izd. Akad. Nauk. ArmSSR (1970), p. 465.
2. V. Veksler, in: Proceedings of the Symposium on High Energy Accelerators (CERN European Organization for Nuclear Research), Geneva, Vol. 1 (1956), p. 80.
3. V. Veksler et al., in: Proceedings of the Sixth International Conference on High Energy Accelerators, Cambridge (1967), p. 289.
4. W. Chupp et al., in: Proceedings of the Ninth International Conference on High Energy Accelerators, Stanford (1974), p. 235.
5. G. Andelfinger et al., ibid in: Proceedings of the Ninth International Conference on High Energy Accelerators, Stanford (1974), p. 218.