Is this a relation of yours? http://history.cs.ncl.ac.uk/anniversaries/40th/images/ibm360_672/slide17.htm l http://history.cs.ncl.ac.uk/anniversaries/40th/images/ibm360_672/15.html Bill S. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus