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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Publication date
Application filed by А.С. ВирновскийfiledCriticalА.С. Вирновский
Priority to SU13ApriorityCriticalpatent/SU69416A1/en
Application grantedgrantedCritical
Publication of SU69416A1publicationCriticalpatent/SU69416A1/en