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 filed by Ю.Н. СелифонтоваfiledCriticalЮ.Н. Селифонтова
Application grantedgrantedCritical
Publication of SU23268A1publicationCriticalpatent/SU23268A1/en