Abbemuseum, ZERO / Nul # HEINZ MACK # Jan van Toorn design, 1973, B++ condition
Heinz Mack, Piene, Gunther Uecker, ZERO # LICHTRAUM ( Fontana) 1964 # 1992, nm-
Zero, Mack, Piene# NEUE GRUPPE SAAR# 1961, nm