^ See also The Independent (Feb. 6, 1908) p. 274 online

^ Roosevelt,
"Special message to Congress, January 31, 1908," in Elting E. Morison, ed., The  Letters of Theodore Roosevelt (Harvard UP, 1952) vol 5 pp. 1580, 1587; online version at UC Santa Barbara, “The American Presidency Project”

^ Miller 1992, pp. 483–485.

^ Brands 1997, p. 626.

^ Miller 1992, pp. 488–489.

^ Solvick, Stanley D. (1963). "William Howard Taft and the Payne-Aldrich Tariff". The Mississippi Valley Historical Review. 50 (3): 424–442. doi:10.2307/1902605. JSTOR 1902605.

^ "President Roosevelt's African Trip". Science. 28 (729): 876–877. December 18, 1908. Bibcode:1908Sci....28..876.. doi:10.1126/science.28.729.876. JSTOR 1635075. PMID 17743798.

^ Jump up to: a b "Roosevelt African Expedition Collects for SI". Smithsonian Institution Archives. Archived from the original on October 9, 2012. Retrieved April 10, 2012.

^ Cevasco, George A. & Harmond, Richard P. (2009). Modern American Environmentalists: A Biographical Encyclopedia. JHU Press. p. 444. ISBN 978-0-8018-9524-1. Archived from the original on November 16, 2015. Retrieved October 17, 2015.

^ O'Toole 2005, p. 67.

^ Roosevelt, Theodore (1910). African Game Trails. New York, C. Scribner's sons.

^ Miller 1992, p. 505.

^ Miller 1992, pp. 505–509.

^ Miller 1992, p. 511.

