Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US07/542,613external-prioritypatent/US5121290A/en
Application filed by At & T CorpfiledCriticalAt & T Corp
Priority to SG115494ApriorityCriticalpatent/SG115494G/en
Publication of SG115494GpublicationCriticalpatent/SG115494G/en