Omaha and vicinity / U.S. Geological Survey ; Charles D. Walcott, director ; Henry Gannett, chief topographer ; Jno. H. Renshawe, topographer in charge ; control by Geo. T. Hawkins ; Mo. river from surveys by Mo. Riv. Com. ; topography by H.S. Wallace.Geological Survey (U.S.)1898]"Nebraska, Iowa"--Upper right margin."Surveyed in 1893 and 1898."Relief shown by contours.cartographic