The model book of Giovannino de Grassi. Cassaf.I.21 of the Biblioteca Civica 'Angelo Mai' in Bergamo. Facsimile and commentary. 1 issue and 1 volume. 27 x 19,5 cm. OKarton with thread stitching in velvet bag or cover, together in OPapp cassette (with mounted RSchild). ==References====External links== Giovannino de Grassi was a sculptor and draftsman, but also one of the builders of the Milan Cathedral, and also worked at the court of the Visconti. ==References====External links== It contains 77 drawings and a 24-letter alphabet. – As good as new.