Graphic. WTC aircraft debris impact, Sept 11, 2001.
FEMA - Therese McAllister, Therese McAllister, Jonathan Barnett, John Gross, Ronald Hamburger, Jon Magnuson
"Figure 1-4 Areas of aircraft debris impact." <a rel="nofollow" class="external free" href="http://www.fema.gov/pdf/library/fema403_ch1.pdf">http://www.fema.gov/pdf/library/fema403_ch1.pdf</a> (page 6)