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3. I. E. Kontorovich, collection: Increasing Machine Service Life [in Russian], Mashgiz, 1956.
4. H. Wiegand and M. Koch, Metalloberflache, no. 3, 12, 1958.
5. I. V. Kudryavtsev, I. B. Meerovich, N. M. Savvina, and V. I. Taft, MiTOM, no. 10, 1963.