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2. J.F. Ziegler: New Uses of Ion Accelerators, Plenum Press, New York, 1975.
3. J.W. Mayer, E. Rimini: Ion Beam Handbook for Material Analysis, Acad. Press, London, 1977.
4. Edwards High Vacuum, Manor Royal, Crawley, Sussex, England.
5. Panmure Instruments Ltd., Bone Lane Industrial Estate, Newbury, Berks, England.