Where to Now? Decreasing Options for Displaced Iraqis / Migration Policy Institute, October 2007
http://www.migrationinformation.org/Feature/display.cfm?id=644
Andrew Harper
"No one knows the exact number of Iraqis who were displaced either before or after the March 2003 invasion. However, the most accepted estimate is that over 4 million, or just over one in six, are either displaced within Iraq or have fled abroad."