Version history for Norman, Laura M., Gishey, Michael, Gass, Leila, Yanites, Brian, Pfeifer, Edwin, Simms, Ron, and Ahlbrant, Ray, 2006, Processed 1938 aerial photography for selected areas of the lower Colorado River, southwestern United States: U.S. Geological Survey Open-File Report 2006-1141 [available on the World Wide Web at URL http://pubs.usgs.gov/of/2006/1141/ ] Version 1.0, May 10, 2006 Initial release online at http://pubs.usgs.gov/of/2006/1141/