Etching on zinc plate from the 'Quattro acqueforti originali ed un disegno fuori testo presentati da Guido Ballo' portfolio; Paper size 39.5 x 26 cm; Image size 18.2 x 20 cm; Frame size 44 x 39.5 cm; Edition 30 + V + 5 p.a .; Signed lower right in pencil by the Artist; Proof of Artist; Editions La Salita , Rome, 1958; References Sandro Parmiggiani, Enrico Della Torre, General catalog of graphic works 1952-2012, Skira Edizioni, p. 93, pl. 47; Certificate of guarantee.