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Priority claimed from GB878717172Aexternal-prioritypatent/GB8717172D0/en
Priority claimed from GB878718351Aexternal-prioritypatent/GB8718351D0/en
Application filed by Emi Plc ThornfiledCriticalEmi Plc Thorn
Priority claimed from EP88306636Aexternal-prioritypatent/EP0300754B1/de
Application grantedgrantedCritical
Publication of ATE98801T1publicationCriticalpatent/ATE98801T1/de