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Priority claimed from GB848412355Aexternal-prioritypatent/GB8412355D0/en
Application filed by British TelecommfiledCriticalBritish Telecomm
Priority claimed from EP85902095Aexternal-prioritypatent/EP0181880B1/de
Application grantedgrantedCritical
Publication of ATE45843T1publicationCriticalpatent/ATE45843T1/de