Physical description for original version: 27 p. : 28 cm
書誌注記
Bibliography: p. 7
原資料等に関する注記
原資料の出版事項: Broomall, PA ; Washington, D.C. : U.S. Dept. of Agriculture, Forest Service, Northeastern Forest Experiment Station : For sale by the Supt. of Docs., U.S. G.P.O., 1984