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Publication date
Priority claimed from GB19710/60Aexternal-prioritypatent/GB940457A/en
Priority claimed from GB2006360Aexternal-prioritypatent/GB947593A/en
Priority claimed from GB20062/60Aexternal-prioritypatent/GB952338A/en
Application filed by Bell Telephone MfgfiledCriticalBell Telephone Mfg
Application grantedgrantedCritical
Publication of BE604528RpublicationCriticalpatent/BE604528R/en