No idea of a link to it, though.
Here you go: http://www.flounder.com/bush.htm
Just send your friend to this site. http://www.flounder.com/bush.htm
It addresses the th in the CBS example and everything else. If anyone reads this and still thinks the memo is genuine, they are simply in complete denial.
There is enough doubt that CBS must produce the original of this memmo. No 3rd or 5th or 30th generation copies, faxes or scans. And the original needs to be verified by a number of outside experts.
If they can not produce the original they should not have run this story.
I know you wanted a link, not my opinion. Sorry.
This is the best link ever on the subject. He explains the CBS underlined "th" as not a superscript, but a ligature.