Não informado. (2002). Journal of Transportation and Statistics. US Department of Transportation, Bureau of Transportation Statistics.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Journal of Transportation and Statistics. Washington: US Department of Transportation, Bureau of Transportation Statistics, 2002.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Journal of Transportation and Statistics. US Department of Transportation, Bureau of Transportation Statistics, 2002.
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