The Valley of the Cobras. 1957. EO. 4th plate 20 bis. Yellow cloth spine. White and red checked endpapers. Inner hinges reinforced with kraft tape, some tape marks on endpapers, bottom of spine and corners slightly worn, discreet signatures. With The Secret of the Unicorn. 1962. 4th plate 31 bis. Red cloth spine, light blue endpaper. Average condition, spine damaged, endpaper split, corners worn, various wear and tear.

Composed of several subsidiaries, the Drouot Group is a major player in the art market. Hôtel Drouot, located in the heart of Paris, has been the world's largest public auction center since 1852. 15 salerooms are available to more than 70 auction houses. The emulation generated by an annual offer of 230,000 artworks from 21 major specialities - from Antiquity to street art - attracts some 3,000 visitors every day. The Group's digital platform, Drouot.com, offers digital sales - Live auctions (live broadcasting and participation in auctions), Online-only auctions (dematerialised auctions) and Buy Now sales (sales of lots at fixed prices). Nearly 2 million items are offered annually by 600 auction houses. Auction news is reported every week in La Gazette Drouot, the leading weekly magazine for the art market and culture published by Auctionspress.