in addition to the Abilene connect, CBS had this to say in a memo to it's affiliate (see preponderance of evidence link on drudge):
CBS News' reporting determined that the source of the memos had access to the documents he provided and an opportunity to obtain copies of them
"CBS News' reporting determined that the source of the memos had access to the documents he provided and an opportunity to obtain copies of them"
You are correct. We have found the source of the documents. Now, I am betting Mapes and Burkett are in this together. I hope they realize they have commited a felony.