Columbia subject headings:
Brecht, Bertolt, 1898-1956--Authorship--Collaboration--Congresses.
Brecht, Bertolt, 1898-1956--Sources--Congresses.
Intellectual property and creative ability--Congresses.
Harvard subject headings:
Brecht, Bertolt, 1898-1956
Brecht, Bertolt, 1898-1956--Authorship--Collaboration.
Copyright--Art--Germany--History.
Copyright--Germany--History.
Princeton subject headings:
Brecht, Bertolt, 1898-1956--Authorship--Collaboration--Congresses.
Brecht, Bertolt, 1898-1956--Sources--Congresses.
Intellectual property and creative ability--Congresses.