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2. B. D. Annin, V. O. Bytev, and S. I. Senashov, Group Properties of the Equations of Elasticity and Plasticity (Nauka, Novosibirsk, 1983) [in Russian].
3. R. Hill, Mathematical Theory of Plasticity (Gostekhteoretizdat, Moscow, 1956) [Russian translation].
4. W. Prager, “Three-Dimensional Plastic Flow under Uniform Stress," Mekhanika, No. 3, 23–27 (1958) )
5. D. D. Ivlev, L. A. Maksimova, R. I. Nepershin, et al., Limiting State of Deformable Bodies and Rocks (Fizmatlit, Moscow, 2008) [in Russian].