1. R. M. Barrer, Diffusion in and Through Solids, 2nd Edn, Cambridge University Press, Cambridge, 1951.
2. W. Jost, Diffusion, Academic Press, New York, 1960.
3. C. E. Rogers, In: Engineering Design for Plastics, ed. E. Baer, Reinhold Publ. Corp., New York, 1964, chap. 9.
4. C. E. Rogers, In: Physics and Chemistry of the Organic Solid State, Vol. II, eds D. Fox, M. M. Labes and A. Weissberger, Interscience Publ., New York, 1965, chap. 6.
5. P. Meares, Polymers: Structure and Bulk Properties, Van Nostrand, London, 1965, chap. 12.