http://www.usatoday.com/news/nation/2006-09-11-sept11-remains_x.htm
By contrast, identification work at the Pentagon and in Shanksville, Pa., where two other passenger jets crashed on 9/11, has been complete since early 2002.
At the Pentagon, military medical examiners linked remains to 179 victims, including passengers aboard American Airlines Flight 77 and people working in the facility.