Revision History for OFR 2005-1413 Joseph S. Duval, John M. Carson, Peter B. Holman, and Arthur G. Darnley Terrestrial Radioactivity and Gamma-ray Exposure in the United States and Canada ----------------------------------------------------- Posted online December 12, 2005 ----------------------------------------------------- Revised and reposted September 14, 2009 The text was reformatted. All data from the DVD have been added to the online version. -----------------------------------------------------