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Keywords from Image Description:
Unterirdischer Krieg. Trenchsystem in World War France de Grabensystem im Ersten Weltkrieg Westfront Originalbeschreibung Englische Darstellung des unterirdischen Krieges an der Westfront published in Die Groe Zeit Illustrierte Kriegsgeschichte second part Berlin Sourcedeclaration From an english journal de Verffentlicht in Die