Legal status (The legal status 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 status listed.)
Expired
Application number
CA615889A
Inventor
W. Hunter Roger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Telephone and Telegraph Corp
Original Assignee
International Telephone and Telegraph Corp
Publication date
Application grantedgrantedCritical
Publication of CA615889ApublicationCriticalpatent/CA615889A/en