Article, 1961, Roland F. Pease Jr. Testimonial of Roland F. Pease Jr. on the blue monochromes seen at the Leo Castelli exhibition, 1961
Photo, 1961 View of the exhibition “Monochrome und Feuer” (MG 17, S 33, S 34, S 35), Museum Haus Lange
Photo, janvier 1961 Yves Klein in front of the sculpture "Pluie Bleue [Blue Rain]" (S 36) during the exhibition "Yves Klein Monochrome und Feuer", Museum Haus Lange