Citation, Documentation of Sources

Q. Do mentions “in passing” of books require complete endnote citations? The author explains he is “naming them as works that exist in the world,” not “citing” them. For example, “Books in my house when I was a child included Mark Twain’s Huckleberry Finn.” I could find nothing in CMOS about this.

A. Books that are mentioned in passing and not relied on for substantive information don’t need to be formally cited in a note or bibliography entry. See also CMOS 13.5.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]