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Priority claimed from GB8040831Aexternal-prioritypatent/GB2090064B/en
Application filed by Haden D H LtdfiledCriticalHaden D H Ltd
Priority claimed from EP81305460Aexternal-prioritypatent/EP0055026B1/en
Application grantedgrantedCritical
Publication of ATE14658T1publicationCriticalpatent/ATE14658T1/en