Physical description for original version: iv, 35 p. : 28 cm
書誌注記
Bibliography: p. 11-13
原資料等に関する注記
原資料の出版事項: [Reston, Va.?] : Dept. of the Interior, U.S. Geological Survey ; Denver, CO : For sale by the Books and Open-File Reports Section, U.S. Geological Survey, 1986