A. Diélectrique-complexe, respectivement, l'ùe de la section efficace, et la longueur du cristal. Page iii En notant que: (rt {r )) = ol t n) avec V:Al le volume, en substituant l'équation (4) dans l'équation (3) il vient (e't'r)=$f ttr

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E. T. Keve and . Et-anis, Studies of phases, phase transitions and properties of some plzt ceramics, Ferroelectrics, vol.7, issue.1, p.77, 1973.
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M. F. Kupriyanov, A. V. Turik, S. M. Zaitsev, and E. G. Et-fesnko, (B-Sc, In), Phase Transitions, vol.19, issue.1, p.65, 1983.
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K. K. Mani and S. N. Et-shringi, Antiferroelectric mode in PbZrO3, Physica Status Solidi (b), vol.1, issue.2, p.49, 1971.
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C. Michel, J. M. Moreau, G. D. Achenbach, R. Gerson, W. Et-janes et al., Atomic structures of two rhombohedral ferroelectric phases in the Pb(Zr, Ti)O3 solid solution series, Solid State Communications, vol.7, issue.12, p.865, 1969.
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K. A. Mùller, Nonlinear Phenomena at phase Transition and Instabilities, 1981.

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T. Riste, E. J. Samuelsen, K. Otnes, and J. Et-feder, Critical behaviour of SrTiO3 near the 105??K phase transition, Solid State Communications, vol.9, issue.17, p.1455, 1971.
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K. Roleder, G. E. Kugel, M. D. Fontana, J. Handerek, S. Lahlou et al., single crystals with low Ti content and a study of the Ti influence, Journal of Physics: Condensed Matter, vol.1, issue.12, p.2257, 1989.
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J. F. Scott and . Balkanski, Light scattering in solids, p.15, 1971.

G. Shirane, K. Suzuki, A. Et-tekeda, and J. , (II) X-ray Study, Journal of the Physical Society of Japan, vol.7, issue.1, p.12, 1952.
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C. P. Slichaer, Priciples of Magnetic Resonance, 1963.

G. 4. Smonlenskii, V. Et-paslmkov, and . Doklady, I 95 I, Alcad.Naalr.,SSSÀ, vol.7, issue.9, p.45

V. J. Tennery, Jourttal of the electrochemiul socieQt, p.2, 1965.

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S. H. Wemple, M. Et-didomenico, . R. Jr, and . Burgess-Édit, Flucntation phenomeno in solids, 1965.

E. A. Zavadsky and Y. M. Et-istchuk, Metastable States in Ferroelectrics, Naukova Dumk4 Kiev, vol.255, 1987.