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2. D. M. Ioffe, Izv. VTI, No. 7 (1950)
3. Candidate's Dissertation [in Russian], MÉI (1952).
4. I. V. Kipriyanov, Trudy TsKTI [in Russian], Book 22, Mashgiz, Moscow (1952); Candidate's Dissertation [in Russian] (1950).
5. A. Ya. Inayatov, Candidate's Dissertation [in Russian], ÉNIN (1953).