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2. L. I. Sedov, Mechanics of Continuous Media [in Russian], Vol. 1, Nauka, Moscow (1973).
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4. E. Cartan, Theory of Spinors, MIT Press, Cambridge, Mass. (1967).
5. V. A. Zhelnorovich, ?Spinor as an invariant object,? Prikl. Mat. Mekh.,30, No. 6 (1966).