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Fotothek df tg Festungsbau Bastion Contregarde Ravelin Hornwerk Kurtine. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung AAA Amsterdam Grundriss Schnitt und perspektivische Ansicht einer Festungsanlage Bastion Ravelin Contregarde Hornwerk Papier Kupferstich cm Festungsbau Bastion Contregarde Ravelin Hornwerk