Besides works by local artists he exhibited works by Piero Manzoni, Christian Megert, Diter Rot, Robert Filliou, Niki de Saint Phalle and Daniel Spoerri.
He was influenced by artists such as Yves Klein, and Lucio Fontana; he was also close to the artists involved in Azimut, such as Piero Manzoni and Enrico Castellani.
In 2012, the Museum of Contemporary Art received 30 contemporary pieces from the 1950s to 1980s, with artworks from Piero Manzoni, Ad Dekkers, Christo, Jules Olitski and Franz Kline, as well as California artists Craig Kauffman and Ron Davis, from the collection of Vance E. Kondon and his wife Elisabeth Giesberger.
Alessandro Manzoni | Piero Sraffa | Piero Manzoni | Piero della Francesca | Piero de' Medici | Alessandro Del Piero | Piero Scaruffi | The Betrothed (Manzoni novel) | Piero Taruffi | Giacomo Manzoni | ''The Baptism of Christ'', by Piero della Francesca | Piero Sicoli | Piero Gleijeses | Piero di Puccio | Piero Corti | Piero Angela | Gian Piero Reverberi | Diego Manzoni | San Piero a Sieve | Piero Tosi | Piero Strozzi | Piero Simondo | Piero Piccioni | Piero Niro | Piero Marini | Piero Mariani (musician) | Piero Malvestiti | Piero Lissoni | Piero Folli | Piero Ferrari |
Like artists Piero Manzoni, Yayoi Kusama, and later Jean-Michel Basquiat, Wiegman was represented by the renowned Gallery Delta in the Netherlands.