TY - RPRT TI - Eighteenth annual report of the United States Geological Survey to the Secretary of the Interior, 1896-1897: Part II - Papers chiefly of a theoretical nature AU - M.W. Davis AU - R. T. Hill AU - T.W. Vaughan AU - W.H. Dall AU - I.C. Russell AU - G. O. Smith AU - J.E. Wolff AU - A. H. Brooks AU - W.S.T. Smith AU - N.S. Shaler AU - G. K. Gilbert PY - 1897 DO - 10.3133/ar18 UR - https://pubs.usgs.gov/publication/ar18 ID - ar18 ER -