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3. E. Yu Zakharov, B.E. Rebchikov, B.D. D’yakov, Ion Exchange Installation in Nuclear Industry, Energoatomizdat, Moscow, 1987, p. 41 (in Russian).
4. Fluka Chemika, Analytica, Sigma–Aldrich Chemie GmbH, Deisenhofen, 1997–1998, p. 632.
5. A.A. Abramson, V.V. Bocharov, G.M. Goevoy, A.D. Mayophis, A.M. Mayophis, R.M. Matashkina, L. Ya Skvirskiy, B.E. Chistiakov, L.A. Lits, Surface Active Agents, Khimiya, Leningrad, 1979, p. 303 (in Russian).