Columbia subject headings:
Eisler, Hanns, 1898-1962--Political and social views.
Music and state.
Music.
Harvard subject headings:
Composers--Correspondence
Eisler, Hanns, 1898-1962
Eisler, Hanns, 1898-1962--Correspondence.
Music theory
Music--History and criticism
Music--Philosophy and aesthetics
Music--Political aspects.
Princeton subject headings: