Polyphonic music in lilypond, while not difficult, uses concepts
that we haven't discussed yet, so we're not going to introduce
-them. Instead, the following sections introduce these concepts
+them here. Instead, the following sections introduce these concepts
and explain them thoroughly.
@seealso
-Learning Manual: @ruser{Voices contain music}.
+Learning Manual: @ref{Voices contain music}.
+
Notation Reference: @ruser{Simultaneous notes}.
@node Songs