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
CA835996A
Inventor
M. Creighton Andrew
R. Wragg William
R. Maxwell Donald
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.)
May and Baker Ltd
Original Assignee
May and Baker Ltd
Publication date
Application grantedgrantedCritical
Publication of CA835996ApublicationCriticalpatent/CA835996A/en