Citation, Documentation of Sources

Q. CMOS 15.19 says, “Two or more works by the same author in the same year must be differentiated by the addition of a, b, and so forth (regardless of whether they were authored, edited, compiled, or translated), and are listed alphabetically by title. Text citations consist of author and year plus letter.” “Conga Line” is a sequel to “Jazz Madness”—published separately but in the same year. My author insists the sequel appear second in the reference list rather than alphabetically. Nothing in the titles indicates that these are companion volumes, but the author is getting petulant. Advice, please!

A. Since the author feels strongly about the matter, if you have the power to show a little flexibility, it would be the gracious thing to do. I can’t think of any way in which this would confuse or inconvenience readers, although if in doubt, it would be easy enough to clarify by annotating the citation, e.g., “(sequel to ‘Jazz Madness’).”