Swain, Comparative Statistics of Railroad Rates, 115-32, quote 132.
Robert Higgs, "Railroad Rates and the Populist Uprising," Agricultural History 44 (July 1970): 291-98.
Mark Aldrich, "A Note on Railroad Rates and the Populist Uprising," Agricultural History 54 (July 1980): 424-32.
Swain, Comparative Statistics of Railroad Rates, 130-32.
Friesen, Canadian Prairies, 208-9.
William Z. Ripley, Railroads: Rates and Regulation (New York: Longmans, Green, 1912), 93-94.