Santos, J. O. dos, A. Homenko, C. Garre, P. L. de M. Cioffi, and S. L. Saykovitch. “ Common Stock Returns of Us Air Transport Companies before and After the September 11th Terrorist Attacks ”. REGE Revista De Gestão, vol. 15, no. 2, June 2008, pp. 53-64, doi:10.5700/issn.2177-8736.rege.2008.36637.