A substrate upon which an advertising message may be printed is releasably attachable to the side of a truck in a way that prevents the substrate from flapping when the truck is moving at high speeds. The upper and rearward edges of the substrate are retained within rigid frames mounted to...http://www.google.fr/patents/US5845423?utm_source=gb-gplus-shareBrevet US5845423 - Advetising substrate attachable to trucks
