In Chicago style, when the title of a source you’re citing contains the title of another work, the formatting depends on whether each title would normally be in quotation marks or italicized.
The “Titles of Works” section of CMOS chapter 8 (especially section 8.163) goes through the formatting for different types of works; for the purpose of illustration, we’ll consider books (italicized) and journal articles (quotation marks) that include the titles of films (italicized) and poems that aren’t large-scale works (quotation marks).
Book title containing a film title: Put the film title in quotation marks.
Leinberger, Charles. Ennio Morricone’s “The Good, the Bad and the Ugly”: A Film Score Guide. Lanham, MD: Scarecrow Press, 2004.
I often see authors using reverse italics (roman type) for this, but CMOS 8.173 and 14.94-95 specify that reverse italics should only be used for other terms that would normally be italicized, like ship names and foreign terms, not for titles of works.
Book title containing a poem title: Put the poem title in quotation marks.
Author, Example. A Brilliant Analysis of John Keats’s “Ode to a Nightingale.” Fake City: Imaginary University Press, 2023.Listen, I tried to find a real book about a single poem, but I couldn’t.
Note that when an italicized title ends with something in quotation marks, the final punctuation also needs to be italicized, which you should ordinarily never do in a citation!
Article title containing a film title: Put the film title in italics.
McDonald, Matthew. “Hitchcock’s Blackmail and the Threat of Recorded Sound.” Music and the Moving Image 8, no. 3 (2015): 40–51.
JSTOR and other databases will often put these titles-within-titles in quotation marks or without any formatting, so you’ll need to look at how the title is formatted on the first page of the article itself.
Article title containing a poem title: Put the poem title in single quotation marks.
Bradford, Adam. “Inspiring Death: Poe’s Poetic Aesthetics, ‘Annabel Lee,’ and the Communities of Mourning in Nineteenth-Century America.” Edgar Allan Poe Review 12, no. 1 (Spring 2011): 72–100.
If you’re copying and pasting the title from a journal database, make sure to have double quotation marks around the whole article title and single quotation marks around the work title within it.