Physical description for original version: iv, 31 p. : 28 cm
書誌注記
Bibliography: p. 28
原資料等に関する注記
原資料の出版事項: Washington, D.C. ; Springfield, VA : U.S. Dept. of Agriculture, Economic Research Service : For sale by the Supt. of Docs., U.S. G.P.O. : NTIS [distributor], 1984