Article, 1961, Roland F. Pease Jr. Testimonial of Roland F. Pease Jr. on the blue monochromes seen at the Leo Castelli exhibition, 1961
Photo, january 1957 Yves Klein during the exhibition "Proposte monocrome, epoca blu", Galleria Apollinaire
Photo, 1961 Paul Wember, Rotraut Uecker and Yves Klein in front of "Column of Fire" during the exhibition "Yves Klein Monochrome und Feuer" at the Museum Haus Lange