1. B.A. Zager, V.G. Tishin, Soviet Phys. Techn. Phys. 9, 234 (1964).
2. A.J. Hatch, Nucl. Instr. & Meth. 41, 261 (1966).
3. B. Bischof, Nucl. Instr. & Meth. 97, 81 (1971).
4. M.S. Livingston, J.P. Blewett, Particle Accelerators (McGraw-Hill, New York, 1962), p. 345, 381.
5. B.H. Smith, Nucl. Instr. & Meth. 18, 19, 184–193 (1962).