Santos, J. O. dos, Homenko, A., Garre, C., Cioffi, P. L. de M. and Saykovitch, S. L. (2008) “ Common stock returns of us air transport companies before and after the september 11th terrorist attacks ”, REGE Revista de Gestão, 15(2), pp. 53-64. doi: 10.5700/issn.2177-8736.rege.2008.36637.