Columbia subject headings:
Composition (Music)--Congresses.
Music--History and criticism--Congresses.
Variations--Congresses.
Harvard subject headings:
Composition (Music)--Congresses.
Music--History and criticism
Variations.
Princeton subject headings:
Composition (Music)--Congresses.
Music theory--Congresses.
Music--21st century--History and criticism--Congresses.
Music--Philosophy and aesthetics--Congresses.