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.)
Publication of BE363913ApublicationCriticalpatent/BE363913A/xx
Priority claimed from US367084Aexternal-prioritypatent/US1903112A/en
Priority claimed from GB2483530Aexternal-prioritypatent/GB335995A/en