Photo, january 1957 Yves Klein during the exhibition "Proposte monocrome, epoca blu", Galleria Apollinaire
Photo, ca. 1960 Yves Klein and Rotraut with Ci-gît l'Espace [Here Lies Space] (RP 3) and the Sponge Relief (RE 20)
Photo, 1959 Yves Klein, Iris Clert and Rotraut at the opening of the exhibition "Bas-reliefs in a sponge forest", Galerie Iris Clert
Photo, 1957 Yves Klein in front of his Sponge Sculpture at the exhibition "Monochrome Propositions of Yves Klein" Gallery One, London