1. R. P. Kambour,Nature 195 (1962) 1299.
2. Idem, J. Poly. Sci. A 2 (1964) 4159.
3. P. Beahan, M. Bevis andD. Hull,Polymer 14 (1973) 96.
4. R. D. Heidenreich, ?Fundamentals of Transmission Electron Microscopy? (Interscience, New York, 1964).
5. R. E. Burge in ?The Interpretation of Ultrastructure? edited by F. E. Lehman (Academic Press, New York, 1962).