Não informado. (1915). Accident prevention magazine. Portland Cement Association.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Accident Prevention Magazine. Chicago, Ill: Portland Cement Association, 1915.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Accident Prevention Magazine. Portland Cement Association, 1915.
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