Signature in pen lower right. Sincron Gallery, Brescia, authenticity certificate on photo. Munari, called to collaborate in the design of some fabrics, during a visit to the factory realizes that a drop of acid comes out of a machine and stains the fabric in a random way. The error is transformed into a decisive element in the decoration of the fabric which is characterized by a unique design and
unrepeatable. With the cuttings taken from the samples of these fabrics, Munari creates a series that he calls for the occasion "Author's Proofs" and which he presents to the public in May 1983.