I am producing a hymnal, using Lilypond and lilypond-book with xelatex. I
would like to insert biblical references in the margin of the page, parallel
with the lyrics.
For example, in "Hark, the Herald Angels Sing", the lyrics "Ris'n with
healing in his wings" would have "Mal. 4:2" in the margin.
In TeX like systems, this is easily done with the \marginnote command.
Is there a practical way of doing this within Lilypond: of inserting
something like \mark or \markup in the \lyricmode environment such that it
will place the comment automatically in the outer margin of the page?