Columbia subject headings:
Microtones--Congresses.
Music--Acoustics and physics--Congresses.
Musical intervals and scales--Congresses.
Harvard subject headings:
Microtones--Congresses.
Microtones--History--Congresses.
Music intervals and scales--Congresses.
Music--Acoustics and physics--Congresses.
Music--History and criticism--Congresses
Musical intervals and scales--Congresses.
Princeton subject headings:
Microtonal music--History--Congresses.
Microtones--Congresses.