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Fotothek df tg Mechanik Hermetik Pyramide. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Frankfurt Main Pyramide Papier Kupferstich cm Mechanik Hermetik Pyramide ppn Druck Deutsche Fotothek gefrdert von der Deutschen Forschungsgemeinschaft Projekt Technikgeschichte Jh Verwalter Dresden Schsische Landesbibliothek