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2. G. G. Lemmlejn and N. V. Gliki, Dokl. AN USSR,94, 473, 1954.
3. A. Williams, Phil. Mag.,2, 635, 1957.
4. W. Burton, N. Cabrera and F. Frank, Phil. Trans.,A243, 299, 1951.
5. H. G. Van Bueren, Imperfections in Crystals, North-Holl. Publ. Co. Amsterdam, 1960. (in Russian, Izd. Inostr. Lit., Moscow, 1962, p. 410).