Columbia subject headings:
Art, Modern--20th century--Themes, motives.
Fourth dimension.
Geometry, Non-Euclidean.
Harvard subject headings:
Art, Modern--20th century--Themes, motives
Fourth dimension.
Geometry, Non-Euclidean.
Princeton subject headings:
Art, Modern--20th century--Themes, motives.
Fourth dimension.
Geometry, Non-Euclidean.