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Priority claimed from US07/157,348external-prioritypatent/USH826H/en
Priority claimed from US07/157,355external-prioritypatent/USH815H/en
Application filed by Shell Int ResearchfiledCriticalShell Int Research
Priority claimed from EP89200374Aexternal-prioritypatent/EP0329254B1/en
Application grantedgrantedCritical
Publication of ATE77643T1publicationCriticalpatent/ATE77643T1/en