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3. Several books on the new materials have now appeared and include:Chemistry of Superconducting Materials, ed. T.A. Vanderah (Noyes Publ., Park Ridge, NJ, 1991); J.C. Phillips,Physics of High-T c Superconductors (Academic Press, New York, 1989);Studies on High-Temperature Superconductors, Vols. 1–6, ed. A.V. Narlikar (Nova Science Publ., New York, 1989–91);Physical Properties of High Temperature Superconductors, Vols. 1–4, ed. D.M. Ginzburg (World Scientific Press, Singapore, 1989).
4. P. Boolchand and D. McDaniel, in:Studies on High-Temperature Superconductors, ed. A.V. Narlikar, Vol. 4 (Nova Science Publ., New York, 1990), p. 143.
5. B.D. Dunlap, J.D. Jorgensen, C. Segre, A.E. Dwight, J.L. Matykiewics, H. Lee, W. Peng and C.W. Kimball, Physica C158(1989)397.