File:Wtc7 collapse progression.png

This is a file from the Wikimedia Commons. Information from its description page there is shown below.
Commons is a freely licensed media file repository. You can help.

Summary

Plan view of 7 World Trade Centre, damage and collapse progression.

Source: NIST, Interim report on 7 World Trade Centre, Appendix L

http://wtc.nist.gov/progress_report_june04/appendixl.pdf

Licensing

	This work is in the public domain in the United States because it is a work prepared by an officer or employee of the United States Government as part of that person’s official duties under the terms of Title 17, Chapter 1, Section 105 of the US Code. See Copyright. Note: This only applies to original works of the Federal Government and not to the work of any individual U.S. state, territory, commonwealth, county, municipality, or any other subdivision. This template also does not apply to postage stamp designs published by the United States Postal Service since 1978. (See 206.02(b) of Compendium II: Copyright Office Practices). It also does not apply to certain US coins; see The US Mint Terms of Use.
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.

File usage

The following pages on Schools Wikipedia link to this image (list may be incomplete):

Collapse of the World Trade Centre

Find out about Schools Wikipedia

Through Schools Wikipedia, SOS Children's Villages has brought learning to children around the world. The world's largest orphan charity, SOS Children brings a better life to more than 2 million people in 133 countries around the globe. Want to learn more? Go to http://www.soschildrensvillages.org.uk/sponsor-a-child