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2. A. Brukanov, V. Rebelsky, Hot Closed-Die Forging, Moscow, GNTIML (1962) (in Russian)
3. G.L. Teterin et al., Kuznechno-Shtanmpovochnoe proizvodstvo 7 (1966) 6–9 (in Russian)
4. Forging preform design with shape complexity control in simulating backward deformation
5. A.D. Tomlenov, Theory of plastic deformation of metals, Moscow, Mashinostroenie (1972) (in Russian)