Columbia subject headings:
Art, German--20th century--History.
Group work in art--Germany--Munich--History.
Gruppe SPUR--History.
Harvard subject headings:
Art, Modern--20th century
Artistic collaboration--History--20th century.
Group work in art--History--20th century.
Gruppe SPUR.
Princeton subject headings:
Artistic collaboration--History--20th century.
Arts, Modern--20th century.
Group work in art--History--20th century.
Gruppe SPUR.