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Keywords from Image Description:
Fotothek df tg Geometrie Instrument Proportion Kugel Polyeder. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung Nr Frankfurt Main Wrfel Kugel Tetraeder und Isokaeder Papier Kupferstich cm Geometrie Instrument Proportion Kugel Polyeder ppn Druck Deutsche Fotothek gefrdert von der Deutschen Forschungsgemeinschaft