O'Connor, T., & Kristoff, J. M. (1990). Soil survey of Sioux County, Iowa. [Washington, D.C.]: The Service.
Chicago Style CitationO'Connor, Thomas, and Joseph M. Kristoff. Soil Survey of Sioux County, Iowa. [Washington, D.C.]: The Service, 1990.
MLA CitationO'Connor, Thomas, and Joseph M. Kristoff. Soil Survey of Sioux County, Iowa. [Washington, D.C.]: The Service, 1990.
Warning: These citations may not always be 100% accurate.