The order of authors in a reference list

This one is a bit tricky, and I had to confirm it in CMS17. What's the order of entries in an author-date reference list when there is more than one author?

That one is easy, you order put it after the single-author entry and order by date.

But what happens when there are multiple entries with multiple authors with the same leading author?

That one took a bit of digging, and it's not spelled out clearly in the text, but check the examples in CMS17 §15.16. The examples show that they are alphabetized by the Last name of the next author and then date, in the case of multiple entries. If the second author is identical, but the third authors differ, then alphabetize by that author and order by date. And so on.

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