Columbia subject headings:
Art and society.
Art brut.
Art, Modern--20th century.
Art.
Outsider art.
Harvard subject headings:
Art and society
Art brut.
Art, Modern--20th century
Art, Primitive.
Outsider art
Princeton subject headings:
Art and society.
Art brut.
Art, Modern--20th century.
Art.
Outsider art.