The Collapse of the WTC by Kevin Ryan, Underwriters Laboratories.
"This story just does not add up. If steel from those buildings did soften or melt, I’m sure we can all agree that this was certainly not due to jet fuel fires of any kind, let alone the briefly burning fires in those towers."
http://www.septembereleventh.org/newsarchive/2004-11-11-ryan.php
Kevin Ryan was fired from his job at UL a week after this was published.