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Priority claimed from US07/189,540external-prioritypatent/US4817783A/en
Priority claimed from US07/333,136external-prioritypatent/US4969389A/en
Application filed by Raymond Keith FosterfiledCriticalRaymond Keith Foster
Application grantedgrantedCritical
Publication of ATE87587T1publicationCriticalpatent/ATE87587T1/en