Article, 1961, Roland F. Pease Jr. Testimonial of Roland F. Pease Jr. on the blue monochromes seen at the Leo Castelli exhibition, 1961
Photo, 1960 Yves Klein, Rotraut, Jean Tinguely and Eva Aeppli at the opening of the exhibition "Yves le Monochrome" at the Galerie Rive Droite
Photo, 1959 International collaboration between artists and architects in the realisation of the new Gelsenkirchen Opera House