Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Application filed by Н.С. ДобровольскийfiledCriticalН.С. Добровольский
Priority to SU38171ApriorityCriticalpatent/SU14725A1/en
Application grantedgrantedCritical
Publication of SU14725A1publicationCriticalpatent/SU14725A1/en