1. 1) A. S. Nowick and B. S. Berry: Anelastic Relaxation in Crystalline Solids, Academic Press, New York, (1972).
2. 2) F. Povolo: J. Mater. Sci., 24 (1989), 1513.
3. 3) E. Roubine: Distribution-Signal, Editions Eurolles, Paris, (1982).
4. 4) I. S. Gradshteyn and I. M. Ryzhik: Table of Integrals, Series and Products, Academic Press, New York, (1965), p. 211.
5. 5) F. Povolo: Phys. Status Solidi (a), 103 (1987), 693.