Abel, W. (1980). Agricultural fluctuations in Europe from the thirteenth to the twentieth centuries. St. Martin's Press.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रAbel, Wilhelm. Agricultural Fluctuations in Europe from the Thirteenth to the Twentieth Centuries. New York: St. Martin's Press, 1980.
एमएलए (9वां संस्करण) प्रशस्ति पत्रAbel, Wilhelm. Agricultural Fluctuations in Europe from the Thirteenth to the Twentieth Centuries. St. Martin's Press, 1980.
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