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2. J.R. Lindbeck, M.W. Williams and R.M. Wygant: Manufacturing Technology (Prentice Hall, Englewood Cliffs, N.J. 1990).
3. S. Kalpakjian: Manufacturing Engineering and Technology (Prentice Hall, Upper Saddle River, N.J. 2001).
4. D. Schmoeckel and D. Hemyari: The realization of warm forging's full potential (IMechE 1998).
5. Schuler: Metal Forming Handbook (Springer, Verlag Berlin Heidelberg, New York 1998).