Não informado. (1961). Agricultural Economic Report. U.S. Department of Agriculture, Economics, Statistics and Cooperative Service.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Agricultural Economic Report. Washington: U.S. Department of Agriculture, Economics, Statistics and Cooperative Service, 1961.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Agricultural Economic Report. U.S. Department of Agriculture, Economics, Statistics and Cooperative Service, 1961.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.