The enemy within
Subtitle: the inside story of German sabotage in America
By: by Captain Henry Landau, profusely illustrated with photographs and photostatic copies of original documents.
Publisher: G. P. Putnam's Sons
Published: 1937
Place of publication: [New York]
Subjects: World War, 1914-1918 -- Secret service -- Germany.; World War, 1914-1918 -- United States.; Sabotage.