I've now made my first round of notes on the published Herbert songs, listing lyricist, date of publication, publisher, and any notes on the publication, like dedication or "sung by _______." For the manuscript, unpublished numbers I've recorded if it's a composer or copyist score, lyricist if noted, character assigned to sing the number if it were intended for a show, and any other pertinent info.
I have to do the same now for the piano music and the cello-piano duets. I'd rather nap.