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3. E. F. Kryzhanovskaya-Kaplun, Byull. Éksperim. Biol. i Med., No. 5, 45 (1970).
4. E. F. Kryzhanovskaya-Kaplun, Proceedings of the Twelfth All-Union Congress of Obstetricians and Gynecologists [in Russian], Moscow (1971), p. 213.
5. I. D. Lanovoi, Akush. i Gin., No. 3, 54 (1966).