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Fotothek df tg Architektur Festung Kurtine Bastei Ravelin Grundriss Streichwehr. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Lib Cap Figur Frankfurt Main Aufstellung der Streichwehr an Bollwerken der Festungsbauten Bastei Kurtine Ravelin Papier Kupferstich cm Architektur Festung Kurtine Bastei Ravelin Grundriss