Polak, J. B. K., & Van Der Kamp, J. (1980). Changes in the field of transport studies: Essays on the progress of theory in relation to policy making. Martinus Nijhoff Pub..
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रPolak, J. Band Kamp, और J.B Van Der Kamp. Changes in the Field of Transport Studies: Essays on the Progress of Theory in Relation to Policy Making. Martinus Nijhoff Pub., 1980.
एमएलए (9वां संस्करण) प्रशस्ति पत्रPolak, J. Band Kamp, और J.B Van Der Kamp. Changes in the Field of Transport Studies: Essays on the Progress of Theory in Relation to Policy Making. Martinus Nijhoff Pub., 1980.
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