Physical description for original version: ii, 47 p. : 28 cm
書誌注記
Includes bibliographies
原資料等に関する注記
原資料の出版事項: Pgh. [i.e. Pittsburgh], PA. ; Washington, D.C. : U.S. Dept. of the Interior, Bureau of Mines : For sale by the Supt. of Docs., U.S. G.P.O., 1984