What is left of the architecture of the 1920s? In 1929 Walter Müller-Wulckow illustrated his three books "Deutsche Baukunst der Gegenwart" in the Blauen Bücher series with 323 photographs of 248 buildings typical of the decade. In the last 15 years Peter Bläsing has sought out these architectural works and photographed them, when possible from the original photographic angle.