Alkalic rocks and resources of thorium and associated elements in the Powderhorn District, Gunnison County, Colorado / by Jerry C. Olson and David C. Hedlund.
出版資料
[Reston, Va.?] : U.S. Dept. of the Interior, Geological Survey ; Washington, D.C. : For sale by the Supt. of Docs., U.S. G.P.O., 1981 i.e. 1980.
