1. . R. N. Haward, in Molecular Behaviour and the Development of Polymer Materials, ed. A. Ledwith and A. M. North. Chapman and Hall, London, 1975.
2. . A. M. North, in Molecular Behaviour and the Development of Polymer Materials, ed. A. Ledwith and A.M. North. Chapman and Hall, London, 1975.
3. . F. Bueche, Physical Properties of Polymers. Interscience, New York, 1962.
4. . J. Crank and G. S. Park, ed., Diffusion in Polymers. Academic Press, London, 1968.
5. . M. Heskins and J. E. Guillet, Macromolecules, 3, 224 (1970).