1. Findley WN, Lai JS, Onaran K (1976) Creep and Relaxation of Nonlinear Viscoelastic Materials. Amsterdam New York Oxford
2. Menges G, Schmachtenberg E (1983) Kunststoffe 73:543?546
3. O'Connor DG, Findley WN (1962) Influence of normal stress on creep in tension and compression of polyethylene and rigid polyvinyl chloride copolymer. ASME, Paper No. 61-QA-35
4. Leipholz H (1968) Einf�hrung in die Elastizit�tstheorie. Karlsruhe
5. Benham PP, Hutchinson SJ (1971) Polym Eng Sci 11:335?343