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Priority claimed from US06/685,506external-prioritypatent/US4581436A/en
Priority claimed from US06/685,505external-prioritypatent/US4544732A/en
Priority claimed from US06/695,511external-prioritypatent/US4579931A/en
Application filed by Shell Int ResearchfiledCriticalShell Int Research
Priority claimed from EP19850201978external-prioritypatent/EP0195138B1/en
Application grantedgrantedCritical
Publication of ATE63934T1publicationCriticalpatent/ATE63934T1/en