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Priority claimed from US06/909,133external-prioritypatent/US4721809A/en
Priority claimed from GB878710529Aexternal-prioritypatent/GB8710529D0/en
Application filed by American Home ProdfiledCriticalAmerican Home Prod
Priority claimed from EP87308082Aexternal-prioritypatent/EP0260901B1/de
Application grantedgrantedCritical
Publication of ATE61349T1publicationCriticalpatent/ATE61349T1/de