Camargos, M. A. de, and J. A. R. Romero. “ Reaction of Sao Paulo Stock Exchange Corporative Events: A Test of the Efficient Market Hypothesis ”. REGE Revista De Gestão, vol. 13, no. 3, Sept. 2006, pp. 57-74, doi:10.5700/issn.2177-8736.rege.2006.36566.