1. M. V. Pirani, German Patent DP 188466 (February 1905).
2. H. R. Smith, C. d'A. Hunt, C. W. Hanks, Proceedings of the 3rd Conference on Reactive Metals, Buffalo 1958 (AIME, Interscience, New York, 1958) p. 131.
3. AEC-TID 7546;J. A. Stohr,1957
4. See, for example,R. M. Silva (Ed.) Proceedings of the 2nd Electron Beam Processing Seminar, Frankfurt 1972 (Universal Technology Corporation, Dayton, Ohio, 1972).
5. S. Schiller,ibid, p. 1b1.