National Research Council (U.S.). Highway Research Board. (1973). Freeway operational improvements. National Academy of Science - National Research Council.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNational Research Council (U.S.). Highway Research Board. Freeway Operational Improvements. Washington, D.C: National Academy of Science - National Research Council, 1973.
एमएलए (9वां संस्करण) प्रशस्ति पत्रNational Research Council (U.S.). Highway Research Board. Freeway Operational Improvements. National Academy of Science - National Research Council, 1973.
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