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
Article, 1961, Roland F. Pease Jr. Testimonial of Roland F. Pease Jr. on the blue monochromes seen at the Leo Castelli exhibition, 1961