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Keywords from Image Description:
Fotothek df tg Geometrie Planimetrie Proportion Kugel Polyeder. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung Nr Frankfurt Main proportionale Verwandlung von Kugeln und Polyedern Papier Kupferstich cm Geometrie Planimetrie Proportion Kugel Polyeder ppn Druck Deutsche Fotothek gefrdert von der Deutschen