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Priority claimed from GB858525587Aexternal-prioritypatent/GB8525587D0/en
Priority claimed from GB868618014Aexternal-prioritypatent/GB8618014D0/en
Application filed by Robson Peter M, John Hewitt KeighleyfiledCriticalRobson Peter M
Priority claimed from EP86307889Aexternal-prioritypatent/EP0220869B1/de
Application grantedgrantedCritical
Publication of ATE58629T1publicationCriticalpatent/ATE58629T1/de