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Priority claimed from US06/689,385external-prioritypatent/US4680972A/en
Priority claimed from US06/798,169external-prioritypatent/US4679438A/en
Application filed by Dynisco IncfiledCriticalDynisco Inc
Application grantedgrantedCritical
Publication of ATE73230T1publicationCriticalpatent/ATE73230T1/de