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.)
Filing date
Publication date
Application filedfiledCritical
Priority to SU1820884ApriorityCriticalpatent/SU491771A1/ru
Application grantedgrantedCritical
Publication of SU491771A1publicationCriticalpatent/SU491771A1/ru