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 GB4379/61Aexternal-prioritypatent/GB920229A/en
Application filed by Bell Telephone MfgfiledCriticalBell Telephone Mfg
Publication of BE613517ApublicationCriticalpatent/BE613517A/en