Não informado. (1957). Traffic safety. National Safety Council.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Traffic Safety. Chicago, Ill: National Safety Council, 1957.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Traffic Safety. National Safety Council, 1957.
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