Report of a geological survey of Wisconsin, Iowa, and Minnesota; and incidentally of a portion of Nebraska Territory. Made under instructions from the United States Treasury department
Owen, David Dale, 1807-1860; United States. General Land Office; Leidy, Joseph, 1823-1891; Norwood, J. G. (Joseph Granville), 1807-1895; Parry, C. C. (Charles Christopher), 1823-1890; Pratten, Henry; Shumard, B. F. (Benjamin Franklin), 1820-1869; Whittlesey, Charles, 1808-1886