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Priority claimed from US07/032,562external-prioritypatent/US4718567A/en
Priority claimed from US07/139,745external-prioritypatent/US4776475A/en
Application filed by Polytop CorpfiledCriticalPolytop Corp
Application grantedgrantedCritical
Publication of ATE72799T1publicationCriticalpatent/ATE72799T1/de