Düsseldorf: Galerie Schmela, 1959 (03), 20,9×29,4 cm [full spread]. Bifolium. Exhibition / performance invitation for the first solo exhibition of Piene who on the opening night performed Archaic Light Ballet. Embossed piece hand-glued on cover, while inside opens up to a tipped in plate. One of the most coveted invitations published by Galerie Schmela.