Pegrum, D. F. (1973). Transportation: Economics and public policy (3d ed.). R. D. Irwin.
Chicago Style aipamenaPegrum, Dudley Frank. Transportation: Economics and Public Policy. 3d ed. Homewood, Ill.: R. D. Irwin, 1973.
MLA aipamenaPegrum, Dudley Frank. Transportation: Economics and Public Policy. 3d ed. R. D. Irwin, 1973.
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