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Priority claimed from GB858531869Aexternal-prioritypatent/GB8531869D0/en
Priority claimed from GB858531870Aexternal-prioritypatent/GB8531870D0/en
Application filed by British TelecommfiledCriticalBritish Telecomm
Priority claimed from EP86310194Aexternal-prioritypatent/EP0234127B1/de
Application grantedgrantedCritical
Publication of ATE60451T1publicationCriticalpatent/ATE60451T1/de