Article, 1961, Roland F. Pease Jr. Testimonial of Roland F. Pease Jr. on the blue monochromes seen at the Leo Castelli exhibition, 1961
Exhibition, 31 May 1957 - 23 Jun 1957 Yves Propositions monochromes Galerie Schmela, Düsseldorf, Germany
Photo, january 1957 Yves Klein during the exhibition "Proposte monocrome, epoca blu", Galleria Apollinaire
Photo, 1957 Yves Klein hanging his works for the exhibition "Yves Propositions monochromes", Galerie Schmela