Não informado. (1917). NATIONAL SAFETY NEWS. National Safety Council.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. NATIONAL SAFETY NEWS. Chicago, Ill: National Safety Council, 1917.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. NATIONAL SAFETY NEWS. National Safety Council, 1917.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.