Abel, W. (1980). Agricultural fluctuations in Europe from the thirteenth to the twentieth centuries. St. Martin's Press.
Չիկագոյի ոճի (17րդ խմբ.) մեջբերումAbel, Wilhelm. Agricultural Fluctuations in Europe from the Thirteenth to the Twentieth Centuries. New York: St. Martin's Press, 1980.
MLA (9րդ խմբ.) ՄեջբերումAbel, Wilhelm. Agricultural Fluctuations in Europe from the Thirteenth to the Twentieth Centuries. St. Martin's Press, 1980.