Subscribe to The Chicago Manual of Style Online
Citation, Documentation of Sources
Q. How do I cite a direct quote correctly if I don’t have all the information? Here’s all I have: Catherine Bertini, U.N. World Food Programme. There is no actual book, magazine, journal, or other source named; no date or page number. I’ve combed the Chicago TOC for a clue. Sorry if I’ve missed the obvious.
A. The reason you won’t find this in CMOS is that it’s poor scholarship to quote someone if you can’t cite the source of the quotation. What you have here is more like a rumor. If you can’t find more information about when or where this person spoke, you should perhaps reconsider using her words in your document.