United States. Soil Conservation Service. Erosion in Washington: Causes and effects. s.n..
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रUnited States. Soil Conservation Service. Erosion in Washington: Causes and Effects. [United States: s.n..
एमएलए (8वां संस्करण) प्रशस्ति पत्रUnited States. Soil Conservation Service. Erosion in Washington: Causes and Effects. s.n..
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.