Six works: (1) J. Becker and C. von der Osten (ed.). Sigmar Polke. The editioned works
1963-2000. Catalogue raisonné. Ostfildern-Ruit, Hatje Cantz, 2000, 424 p., richly illustrated, orig. boards w. dustwr., large 4to. H. Spielman and F. Baumeister. Willi Baumeister. Werkkatalog der Druckgraphik. Ibid., idem, 2005, 223 p., num. ills., orig. cl. w. dustwr., folio.
-and 4 others, on Jasper Johns, Enrico Baj, Dieter Roth and Hélène Delprat (w. double-p. orig. col. lithogr.). (total 6)