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Priority claimed from GB868622711Aexternal-prioritypatent/GB8622711D0/en
Priority claimed from GB878716162Aexternal-prioritypatent/GB8716162D0/en
Application filed by Emi Plc ThornfiledCriticalEmi Plc Thorn
Priority claimed from EP87308309Aexternal-prioritypatent/EP0261896B1/de
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Publication of ATE89426T1publicationCriticalpatent/ATE89426T1/de