Perpendicular planes Was the working title of a monumental, much larger construction in concrete for the Rotterdam Marconiplein. The concrete sculpture was called perpendicular planes, homage to van Doesburg and Oud. (The architect J. J. P. Oud collaborated with the artist Theo van Doesburg of De Stijl in the nearby housing area Spangen. In 1919 Theo van Doesburg made a color scheme for its architecture. This resulted in a conflict between the architect and the artist. But the stained glass windows above the front doors were executed.)
1986 perpendicular planes, laminated wood (Photograph © Harm de Grijs at the University of Pittsburgh Art Gallery).