Columbia subject headings:
Blumenfeld, Erwin, 1897-1969--Exhibitions.
Citroen, Paul Roelof, 1896-1983--Exhibitions.
Dadaism--Netherlands--Exhibitions.
Photography, Artistic--Exhibitions.
Harvard subject headings:
Blumenfeld, Erwin, 1897---Exhibitions.
Blumenfeld, Erwin, 1897-1969--Exhibitions.
Citroen, Paul Roelof, 1896---Exhibitions.
Citroen, Paul Roelof, 1896-1983--Exhibitions.
Dadaism--Netherlands--Exhibitions.
Photography, Artistic--Exhibitions
Princeton subject headings:
Blumenfeld, Erwin, 1897---Exhibitions.
Citroen, Paul Roelof, 1896-1983--Exhibitions.
Photography, Artistic--Exhibitions.