1. C.J.F. Boltcher, P. Bordewijk, Theory of Electric Polarization, vols I & II, 2nd Ed., Elsevier, New York, 1978
2. Anelastic and Dielectric Effects in Polymeric Solids;McCrum,1967
3. Glasses: Structure by Spectroscopy;Wong,1976
4. Electronic Processes in Non Crystalline Materials;Mott,1971
5. Low-Frequency Conductivity Due to Hopping Processes in Silicon