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2. L. E. Alexander, X-Ray Diffraction Methods in Polymer Science, Krieger Publishing Co. Inc., London (1969).
3. Chapter IV, Polymer Handbook, ed. J. Brandrup and E. H. Immergut, Wiley Interscience, New York (1975).
4. Chapter 3, International Tables for X-ray Crystallography, ed. C. H. Macgillavry and G. D. Rieck, Kynoch Press, Birmingham (1968).
5. A. Avitabile, R. Napolitano, B. Pirrozzi, K. D. Rouse, M. W. Thomas and B. T. M. Willis, J. Polym. Sci., Polym. Lett. Ed., 13,351 (1975).