2 [i.e. Deux] Stenberg 2 [i.e. deux] : la periode laboratoire (1919-1921) du constructivisme russe = 2 Stenberg 2 : the laboratory period (1919-1921) of Russian constructivism : [exposition] avril-mai 1975, Galerie Jean Chauvelin, May-July 1975, Annely Juda Fine Art, London, July-September 1975, Art Gallery of Ontario - Nakov, Andrei B. (Galerie J. Chauvelin ; distribution, Idea-Books, 1975)