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Priority claimed from GB888815487Aexternal-prioritypatent/GB8815487D0/en
Priority claimed from GB888820283Aexternal-prioritypatent/GB8820283D0/en
Application filed by Grace W R & CofiledCriticalGrace W R & Co
Priority claimed from EP19890306588external-prioritypatent/EP0349305B1/en
Application grantedgrantedCritical
Publication of ATE95546T1publicationCriticalpatent/ATE95546T1/en