https://ine.uaf.edu/projects/wtc7/
A Structural Reevaluation of the Collapse of World Trade Center 7
J. Leroy Hulsey, University of Alaska Fairbanks
"The principal conclusion of our study is that fire did not cause the collapse of WTC 7 on 9/11, contrary to the conclusions of NIST and private engineering firms that studied the collapse. The secondary conclusion of our study is that the collapse of WTC 7 was a global failure involving the near-simultaneous failure of every column in the building."