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Priority claimed from GB848405717Aexternal-prioritypatent/GB8405717D0/en
Priority claimed from GB848422094Aexternal-prioritypatent/GB8422094D0/en
Application filed by British Library BoardfiledCriticalBritish Library Board
Priority claimed from EP85301513Aexternal-prioritypatent/EP0155797B1/de
Application grantedgrantedCritical
Publication of ATE44991T1publicationCriticalpatent/ATE44991T1/de