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2. B. B. Broms and A. O. Casbarian, Effects of Rotation of the Principal Stress Axes and of Intermediate Principal Stress on the Shear Strength, Proceeding of the Sixth International Conference on Soil Mechanics and Foundation, Engineering (1965).
3. S. S. Vyalov, Problems of the Theory of Deformability of Cohesive Soils, Osnovaniya, Fundamenti i mekhanika gruntov, 3 (1966).
4. A. N. Zelenin and G. M. Lomize, Stress of Specimens in Compression and Small Plastic Deformations of Soil, Report at the Fifth International Conference on Soil Mechanics and Foundation Engineering [in Russian], Paris (1961).
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