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Keywords from Image Description:
Fotothek df tg Geometrie Planimetrie Proportion Dreieck Viereck Kreis Flche. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung Nr Frankfurt Main proportionale Verwandlung von Dreiecks Vierecks und Kreisflchen Papier Kupferstich cm Geometrie Planimetrie Proportion Dreieck Viereck Kreis Flche ppn Druck