ACKNOWLEDGEMENTS
We thank the researchers who collected and reported the field data, our institutions and the many colleagues who helped us in different ways during this project for their comments and suggestions, especially to Professor Dr. Marcus Aguiar. EDB is grateful for the Ph.D. degree scholarship provided by Capes (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior). EDB and SBLA acknowledge the computational support from Professor Carlos M. de Carvalho at LFTC-DFis-UFPR.