ADD_ACKNOWLEDGER (Figured_bass_position_engraver, note_column);
ADD_ACKNOWLEDGER (Figured_bass_position_engraver, slur);
ADD_END_ACKNOWLEDGER (Figured_bass_position_engraver, slur);
ADD_ACKNOWLEDGER (Figured_bass_position_engraver, note_column);
ADD_ACKNOWLEDGER (Figured_bass_position_engraver, slur);
ADD_END_ACKNOWLEDGER (Figured_bass_position_engraver, slur);