Columbia subject headings:
Beuys, Joseph--Exhibitions.
Klee, Paul, 1879-1940--Exhibitions.
Harvard subject headings:
Beuys, Joseph--Exhibitions.
Klee, Paul, 1879-1940--Exhibitions.
Princeton subject headings:
Beuys, Joseph--Exhibitions.
Klee, Paul, 1879-1940--Exhibitions.