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
Priority claimed from CH414768Aexternal-prioritypatent/CH492397A/de
Application filedfiledCritical
Priority claimed from SU1313311Aexternal-prioritypatent/SU414791A3/ru
Application grantedgrantedCritical
Publication of SU379068A3publicationCriticalpatent/SU379068A3/ru