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Priority claimed from US07/079,024external-prioritypatent/US4762187A/en
Application filed by Apache CorpfiledCriticalApache Corp
Priority claimed from EP88302818Aexternal-prioritypatent/EP0285386B1/de
Application grantedgrantedCritical
Publication of ATE90141T1publicationCriticalpatent/ATE90141T1/de