galerie Delta # ROTTERDAMSE KUNSTKRING # ca.1963, vg++
Gerard Verdijk, Schoonhoven # GERARD VERDIJK ET SES AMIS # invitation,2007, nm
Haags Gemeentemuseum # NUL / ZERO # 1964, nm+++
Henk Peeters, Zero/Nul # ECHT PEETERS # signed , dated ,stitched / 2011, mint
Jan Schoonhoven, Verdijk, Ewerdt Hilgemann # OREZ invitation./ ZERO # 1979, nm
Kunsthalle Nürnberg # JAN SCHOONHOVEN # poster, 1985, A--
Kusama, Henderikse, Schoonhoven, Uecker, Fontana ao. # ZERO / NUL # Stedelijk Museum, 1962, mint-
Zero # JAN SCHOONHOVEN # Centraal Museum Utrecht, 1974, vg