1. P. J. Goodhew, in ?Practical Methods in Electron Microscopy?, edited by A. M. Glauert (North-Holland, Amsterdam, 1972) p. 5.
2. I. S. Brammer, in ?Techniques for Electron Microscopy?, 2nd Edn, edited by M. A. D. H. Kay (Blackwell, Oxford, 1965) p. 356.
3. H. Bartsch, in ?Elektronenmikroskopie in der Fest-koerperphysik?, edited by H. Bethge and J. Heydenreich (Akademie-Verlag, Berlin, 1982) p. 336.
4. W. Kern and C. A. Decker, in ?Thin Film Processes?, edited by J. L. Vossen and W. Kern (Academic, New York, 1978) p. 401.
5. W. Kern, RCA Rev. 39 (1978) 278.