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Fotothek df tg Theosophie Philosophie Metereologie Blitz Donner. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Abbildung Oppenheim Experiment zur Darstellung von Blitz und Donner Papier Kupferstich cm Theosophie Philosophie Metereologie Blitz Donner ppn Druck Deutsche Fotothek gefrdert von der Deutschen Forschungsgemeinschaft