Robert Filliou, Principe d' equivalence, 1968. Mixed Media, wood, iron, felted wool, 200 x 1000 cm.
Robert Filliou, Recherche sur l'origine, 1974. Mixed Media, oil, pastel on canvas, wood, 280 x 8900 cm.
Robert Filliou, Portrait pas fait : Joseph Beuys, 1972. Drawing, ink, pencil and felt pen on canvas, 55 × 38 × 2 cm.