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Priority claimed from US06/286,161external-prioritypatent/US4397308A/en
Priority claimed from US06/367,598external-prioritypatent/US4485808A/en
Application filed by George R HepburnfiledCriticalGeorge R Hepburn
Priority claimed from EP88104254Aexternal-prioritypatent/EP0277663B1/en
Application grantedgrantedCritical
Publication of ATE70964T1publicationCriticalpatent/ATE70964T1/en