lilypond-common-includes/default_author_style.ly

\paper {
  authorMarkup =
    #(make-on-the-fly-markup
      (lambda (layout props m)
        (let ((name (chain-assoc-get 'author:name props #f))
              (trail_name (chain-assoc-get 'author:trail_name props #f))
              (birth_year (chain-assoc-get 'author:birth_year props #f))
              (death_year (chain-assoc-get 'author:death_year props #f))
              (organization (chain-assoc-get 'author:organization props #f))
              (string-present (lambda (str) (and str (not (and (string? str) (string-null? str))))))
              (render_informations (lambda (infolist) (string-append (car infolist) (if (null? (cdr infolist)) "" (string-append " (" (string-join (cdr infolist) ", ") ")")))))
              )
          (interpret-markup layout props
            (if (or (string-present trail_name) (string-present name))
              (render_informations (filter string-present (list
                trail_name
                name
                (if (and (string-present birth_year) (string-present death_year))
                  (ly:format "~a‒~a" birth_year death_year)
                  (if (string-present birth_year)
                    (ly:format "*~a" birth_year)
                    (if (string-present death_year) (ly:format "†~a" death_year) "")))
                organization
              )))
              ""
          ))))
      (make-null-markup)
    )
  poetMarkup = \markup { "Worte:" \fromproperty #'author }
  composerMarkup = \markup { "Weise:" \fromproperty #'author }
  poetAndComposerEqualMarkup = \markup { "Worte und Weise:" \fromproperty #'author }
}