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Îðèãèíàë: Âàíêå Â À, Ëîïóõèí Â Ì, Ñàââèí Â Ë «Ñâåðõìàëîøóìÿùèå óñèëèòåëè öèêëîòþííûõ âîëí» ÓÔÍ 99 545–569 (1969); DOI: 10.3367/UFNr.0099.196912a.0545