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Manuscript Preparation, Copyediting, and Proofreading
Q. Is it okay to use a quotation as a chapter title without enclosing the title in quotation marks or otherwise distinguishing it from other chapter titles that are not quotations? If so, must the quotation be explained, that is, associated with a source, in the text?
A. A quotation that has reached the status of cliché may go without quotation marks or attribution in a title: To Be or Not to Be; Practice Makes Perfect. Other quotations should be quoted. Although it’s standard practice not to attach source notes to display type like book or chapter titles, whenever readers would benefit from knowing the source of a quotation, the writer should explain either in the text or in a note.