Document, 1955 Letter from Yves Klein to Jacques Tournier, author of the weekly "Les Nouvelles littéraires, artistiques et scientifiques".
Photo, 1957 View of Yves Klein's "Aerostatic Sculpture" during his exhibition "Yves Klein: Propositions Monochromes", Galerie Iris Clert
Document, 1958 Letter from Yves Klein to the President of the International Confederation of Atomic Explosions