Q. I have a work written by the Duke of Argyll on Queen Victoria. I assume the citation of his name would be “Argyll, Duke of.” However, should the number of the duke be included to differentiate (i.e., 9th duke in this case)? The book does not list the family name at all, though it is John Douglas Sutherland Campbell. How would one write the bibliographic entry?
A. Let’s assume you’re citing The Life of Queen Victoria, which was published in 1909 with the following title page:
At a minimum, you would stick to the information on the title page, resulting in the following listing in the bibliography:
Argyll, Duke of. The Life of Queen Victoria. London: George Bell and Sons, 1909.
This leaves out the initials for the Order of the Garter (“K.G.”) and the Order of the Thistle (“K.T.”), per CMOS 14.73 (and we’ve also omitted the “The,” which isn’t an important part of the name). To specify which duke, start by adding his name in square brackets (as you might do for a pen name):
Argyll, Duke of [John Douglas Sutherland Campbell]. The Life of Queen Victoria. London: George Bell and Sons, 1909.
If you were to cite several works by that author, including works that were published before he became a duke, you could provide a separate listing under any different name in the form of a cross-reference. For example,
Lorne, Marquis of [John Douglas Sutherland Campbell]. Our Railway to the Pacific. London, 1886.
———. See also Argyll, Duke of.
A similar cross-reference would be added under “Argyll.” See CMOS 14.80, 14.81, and 14.82 for additional considerations and examples. (For citing city and date only for works published before 1900, see CMOS 14.128.)
Finally, if you did want to include the duke’s number—for example, because you’ve cited works by the duke’s father, the 8th Duke of Argyll (George John Douglas Campbell, also a prolific author apparently)—use square brackets: “Argyll, [9th] Duke of.”