Association of American Railroads, Initial Study of Air Transportation, 1944.
2.
Automobile Manufacturers Association, Automobile Facts and Figures, Annual.
3.
Brookings Institution, The American Transportation Problem, 1933.
4.
Detroit City Plan Commission, Preliminary Report on Railroad Facilities, 1943.
5.
Eastern Railway Presidents' Committee on Public Relations, Railroad Facts, Annual.
6.
John H. Frederick, Commercial Air Transportation, Chicago: Richard D. Irwin, Inc., 1942.
7.
Interstate Commerce Commission, Annual Report on the Statistics of Railways in the United States.
8.
D. Philip Locklin, Economics of Transportation, Chicago: Richard D. Irwin, Inc.
9.
Roy S.MacElwee, Port Development, New York: McGraw-Hill, 1925.
10.
Harold M. Mayer, "Localization of Railway Facilities in Metropolitan Centers as Typified by Chicago," TheJournal of Land and Public Utility Economics , Nov. 1944, pp. 299-315.
11.
—, "The Railway Terminal Problem of Central Chicago," Economic Geography, Jan. 1945, pp. 62-76.
12.
P. Harvey Middleton, Freight Transport in the United States, Chicago : Railway Business Association, 1944.
13.
National Aeronautic Association, Joint Airport Users Conference Proceedings, 1944.
14.
National Resources Planning Board, Transportation and National Policy, 1942.
15.
-, The Future of Transportation, 1942.
16.
Report of the Urban Planning Conferences under the Auspices of the Johns Hopkins University, Baltimore: Johns Hopkins Press, 1944, "Transportation," pp. 37-111.
17.
Ladislas Segoe (Ed.), Local Planning Administration , Chicago: International City Managers' Association, 1941, Chap. 7, "Transportation ," pp. 247-314.
18.
Lewis C. Sorrell and Harry A. Wheeler , Passenger Transport in the United States, 1920-1950 , Chicago: Railway Business Association , 1944.
19.
"Transportation: War and Postwar," The Annals of The American Academy of Political and Social Science, Nov. 1943.
20.
U. S. Civil Aeronautics Administration, Statistical Handbook of Civil Aviation, 1944.
21.
U. S. National Interregional Highway Committee, Interregional Highways, H. Doc. 379, 78th Cong., 2d sess., 1944.
22.
Eugene Van Cleef, Trade Centers and Trade Routes, New York: D. Appleton-Century Co., 1937.
23.
Ernest W. Williams, The Outlook for the Railroad Industry, National Planning Associa. tion, 1943.
24.
-, The Outlook for Domestic Air Trans port, National Planning Association, 1943.
