Columbia subject headings:
Cage, John. Variations, no. 2.
Tudor, David, 1926-1996.
Harvard subject headings:
Cage, John. Variations, no. 2.
Tudor, David, 1926-1996--Criticism and interpretation.
Princeton subject headings:
Aleatory music.
Cage, John. Variations, no. 2
Music--20th century--History and criticism.
Tudor, David, 1926-1996.