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Fotothek df tg Architektur Festung Bastion Grundriss Enneagon. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Lib Cap Figur Frankfurt Main Enneagonale Bastionrsfestung Grundriss Papier Kupferstich cm Architektur Festung Bastion Grundriss Enneagon ppn Druck Deutsche Fotothek gefrdert von der Deutschen Forschungsgemeinschaft