1. R. F. Boyer, Polym. Eng. Sci. 8, 161 (1968).
2. J. Heijboer, Br. Polym. J. 1, 3 (1969).
3. R. F. Boyer, Polymer 17, 996 (1976).
4. J. Heijboer, Intern. J. Polym. Mater. 6, 11 (1977).
5. D. J. Meier, ed. Molecular Basis of Transitions and Relaxations (Gordon and Breach Science Publishers, London, 1978).