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Fotothek df tg Festungsbau Zitadelle Bastion Ravelin Redan Glacis Kurtine Contres. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung GGG Amsterdam Perspektivische Ansicht eines Festungsbaus mit Zitadelle Papier Kupferstich cm Festungsbau Zitadelle Bastion Ravelin Redan Glacis Kurtine Contrescarpe ppn Druck