Pegrum, D. F. (1963). Transportation: Economics and public policy. Irwin.
Chicago Style (17. basım) AtıfPegrum, Dudley Frank. Transportation: Economics and Public Policy. Homewood, Ill: Irwin, 1963.
MLA (9th ed.) AtıfPegrum, Dudley Frank. Transportation: Economics and Public Policy. Irwin, 1963.
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