Still, the beginning of the last decade was when historic flags' popularity took off, as important examples began to appear at shows and auctions. In 2002, the flag collection of Boleslaw and Marie-Louise D'Otrange Mastai sold at Sotheby's New York. (The Stars and Stripes: The American Flag as Art and as History From the Birth of the Republic to the Present, which records the collection, has become a major reference for collectors.)