Physical description for original version: 48 p. : 28 cm
書誌注記
Includes bibliographical references (p. 14-15)
原資料等に関する注記
原資料の出版事項: Portland, OR (333 S.W. First Avenue, P.O. Box 3890, Portland 97208-3890) : U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Research Station, [1998]