Geologic processes at the land surface / [electronic resource] / by Howard G. Wilshire ... [et al.].. — Washington : Denver, CO : : U.S. G.P.O. ; : For sale by U.S. Geological Survey, Information Services,, 1996.. — 41 p. : : ill. (some col.), maps (some col.) ; 28 cm. - U.S. Geological Survey bulletin ; 2149.