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Keywords from Image Description:
Fotothek df tg Optik Strahlenoptik Reflexion Spiegel Brennspiegel Parabolspiegel. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Kupferblatt Nr Bamberg Brennspiegel Papier Kupferstich cm Optik Strahlenoptik Reflexion Spiegel Brennspiegel Parabolspiegel ppnX Druck Deutsche Fotothek gefrdert von der Deutschen Forschungsgemeinschaft