https://marianneboeskygallery.com/exhibitions/124/works/artworks-13363-pier-paolo-calzolari-non-studio-per-grande-opera-non-1969-1970/
Pier Paolo Calzolari, Non (studio per grande opera "Non"), 1969-1970 | Boesky Gallery
FactSheet: Certificate of Authenticity signed by PPC
pier paolo calzolari