Article, 1961, Roland F. Pease Jr. Testimonial of Roland F. Pease Jr. on the blue monochromes seen at the Leo Castelli exhibition, 1961
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 View of Yves Klein's "Aerostatic Sculpture" during his exhibition "Yves Klein: Propositions Monochromes", Galerie Iris Clert