This Autographed 24x36 Summer Tour 2009 Concert Poster has been Personally Signed by David Crosby, Stephen Stills & Graham Nash of Crosby, Stills & Nash. This item is 100% Authentic to include a Certificate of Authenticity (COA) / hologram by JSA. The authenticity can be verified on JSA website. This poster has some damage from age and handling. There are some liquid stains in the top left and creases throughout the poster. Please refer to pictures for item's condition prior to purchase.