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3. A. N. Zaidel', Bases of Spectral Analysis [in Russian], Nauka, Moscow (1969).
4. A. N. Zaidel', N. I. Kaliteevskii, L. V. Lipis, and M. P. Chaika, Emission Spectral Analysis of Atomic Materials [in Russian], Fizmatgiz, Moscow (1960).
5. R. R. Shvangiradze, I. L. Vysokova, and O. A. Grushutina, in: Applied Spectroscopy [in Russian], Moscow (1977), p. 232.