↑ A.B. Faust, The German Element in the United States with Special Reference to Its Political, Moral, Social, and Educational Influence. (2 vol 1909), vol 1..
↑ Hans Wilhelm Gatzke, Germany and the United States, a "special Relationship?" (Harvard UP, 1980).
↑ Paul M. Kennedy, The Samoan Tangle: A Study in Anglo-German-American Relations 1878–1900 (University of Queensland Press, 2013).
↑ Holger H. Herwig, Politics of frustration: the United States in German naval planning, 1889–1941 (1976).
↑ Thomas Boghardt, The Zimmermann telegram: intelligence, diplomacy, and America's entry into World War I (Naval Institute Press, 2012).
