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Keywords from Image Description:
Aerologische Ostafrikaexpedition . en Preparation of the ascent of ceiling balloon during the German aerological Expedition to East Africa de Pilotballonaufstieg an der Moribucht des Viktoriasees whrend der Aerologischen Ostafrikaexpedition des Kniglichen Aeronautischen Observatoriums bei Lindenberg Bericht ber die aerologische Expedition