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Priority claimed from US06/520,883external-prioritypatent/US4536497A/en
Priority claimed from US06/520,882external-prioritypatent/US4505904A/en
Application filed by Shell Int ResearchfiledCriticalShell Int Research
Priority claimed from EP84201054Aexternal-prioritypatent/EP0133717B1/en
Application grantedgrantedCritical
Publication of ATE36716T1publicationCriticalpatent/ATE36716T1/en