Perkins to Larrabee, Oct. 31, 1887, Larrabee to Perkins, Nov. 18, 1887, Perkins to Larrabee, Dec. 2, 1887, all in C. E. Perkins, Out Letters/In Letters 3, P 4.11 - P 4.3, CB&Q.
Seligman, "Railway Tariffs," 227-28.
Maury Klein, "Competition and Regulation: The Railroad Model," Business History 64 (Summer 1990), 313-16.
Joseph Schumpeter, "Railway Rate Making: Discussion," American Economic Review 4 (March 1914): 81-100.
Edwin R. A. Seligman, "Railway Tariffs and Interstate Commerce Law," Political Science Quarterly 2 (June 1887): 224-30, quote 229.
See Berk, Louis D. Brandeis 74-81.