Columbia subject headings:
Beuys, Joseph--Criticism and interpretation.
Beuys, Joseph.
Conceptual art--Germany.
Documenta.
Harvard subject headings:
Beuys, Joseph
Beuys, Joseph--Criticism and interpretation.
Conceptual art--Germany.
Documenta (Exhibition)
Documenta.
Princeton subject headings:
Beuys, Joseph--Exhibitions.
Documenta.