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Fotothek df tg Architektur Festung Bastion Grundriss Hexagon Kasematten. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Lib Cap Figur Frankfurt Main Hexagonale Bastionrsfestung Ansicht und Teilgrundriss Papier Kupferstich cm Architektur Festung Bastion Grundriss Hexagon Kasematten ppn Druck Deutsche Fotothek