
source: - "Washboat days". Book by Jeanine Warnod, p. 204, 1972.
I try to make concrete that which is abstract.
source: - Response to questionnaire circulated to the Cubists by Amédée Ozenfant and Le Corbusier, editors of "L'Esprit Nouveau" # 5, February 1921.
source: - "'Chez les cubistes' (in 'Bulletin de la Vie Artistique')". "Juan Gris: His Life and Work". Book by Daniel-Henry Kahnweiler, 1946.
source: - "On the Possibilities of Painting". Lecture, Sorbonne, May 15, 1924.