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Citation, Documentation of Sources
Q. In an informal meeting with a colleague she mentioned a statistic that is of great help with my master’s thesis. How do I cite in text as well as in the bibliography this oral information?
A. A bibliography is better suited for published works than for conversations and informal sources. To cite your friend in the text or in a note, give her name and the date and place. Please see CMOS 14.214 for examples of such citations. (Ideally, you will also be able to explain why she is an authority on the subject.)