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Fotothek df tg Festungsbau Bastion Kurtine Contrescarpe. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung MMM Amsterdam Grundrisse polygonaler Festungsbauten Papier Kupferstich cm Festungsbau Bastion Kurtine Contrescarpe ppn Druck Deutsche Fotothek gefrdert von der Deutschen Forschungsgemeinschaft Projekt