Photo, 1957 Yves Klein at the opening of his exhibition "Yves Propositions monochromes", Galerie Schmela, Düsseldorf
Document, 1957 Invitation card for the double exhibition "Yves Klein: Propositions monochromes" at the Iris Clert and Colette Allendy Galleries
Photo, 1959 International collaboration between artists and architects in the realisation of the new Gelsenkirchen Opera House
Photo, 1957 Yves Klein hanging his works for the exhibition "Yves Propositions monochromes", Galerie Schmela