There are a lot of mini posters on ebay right now, somwhere in America seems to have an inexhaustible supply, this lovely Shell for example
One seller has a few including this one notable for one of the worst puns of all time
How do we rank these mini posters : if they were pages from a book then practically nothing but as genuine lithographs ?
Looking back on my 1930s gem of an advert for LT poster sales it mentions sizes start at 10 by 13 inches so maybe these little babies are under estimated after all.