BALZAC (Honoré de). The Unknown Masterpiece. Paris, Ambroise Vollard, 1931. Small folio, leaves, untrimmed, illustrated cover, slipcase. Edition illustrated by Pablo Picasso with 13 original etchings out of text (including one for the table), 67 woodcut drawings by Georges Aubert and 16 plates with drawings composed of dots and lines. Published in 1931 to celebrate the centenary of its first publication, Le chef-d'œuvre inconnu is a veritable aesthetic plea by Balzac, and a compendium of his thoughts on the painter and his work. Pablo Picasso found the opportunity to represent the different aspects of the painter's relationship with his model, offering us some of his most poetic etchings. Splendid illustrations by Pablo Picasso. Edition of 340 copies, this one of 240 copies on Rives. Pablo Picasso, Catalogue raisonné des livres illustrés, no. 20.