Q. Is it ever acceptable to use both footnotes and endnotes in the same paper, such as to separate citations from longer comments? Or is it permissible to combine both elements into either footnotes or endnotes? I have not been able to find any answer to this in the Manual. Am I just bad at looking? Thanks!
A. Well, since you ask, yes—you are pretty bad at looking. CMOS 13.2 describes typical content for notes (“notes allow space for unusual types of sources as well as for commentary on the sources cited”), and 13.52 lays out the case for endnotes plus footnotes. (“Especially in a heavily documented work, it may be helpful to separate substantive notes from source citations. In such a case, the citation notes should be numbered and appear as endnotes.”)