Não informado. (1957). Foreign agriculture circular. U.S. Department of Agriculture, Foreign Agricultural Service.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Foreign Agriculture Circular. Washington: U.S. Department of Agriculture, Foreign Agricultural Service, 1957.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Foreign Agriculture Circular. U.S. Department of Agriculture, Foreign Agricultural Service, 1957.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.