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
CA748574A
Inventor
M. Robins John
H. Clark Thomas
Beaufoy Raymond
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.)
British Telecommunications PLC
Original Assignee
British Telecommunications PLC
Publication date
Application grantedgrantedCritical
Publication of CA748574ApublicationCriticalpatent/CA748574A/en