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Application filed by М.Б. Гринберг, Г.С. ПетровfiledCriticalМ.Б. Гринберг
Priority to SU177917ApriorityCriticalpatent/SU49218A1/en
Application grantedgrantedCritical
Publication of SU49218A1publicationCriticalpatent/SU49218A1/en