[Reston, Va.] : U.S. Dept. of the Interior, Geological Survey, National Cartographic Information Center (NCIC) ; Washington, D.C. : For sale by the Supt. of Docs., U.S. G.P.O., 1981.
Physical Description
1 folded sheet : col. ill. ; 30 x 23 cm. folded to 23 x 11 cm.