1982-9949 1982-9949 S1982-99492017000200171 10.17058/rea.v25i2.9814 USA 00 05 2017 00 05 2017 25 2 171 195

21 3 3 457-70 59 3 3 297-324 46 2 2 1255-267 30 2 2 15-25 46 4 4 376-99 32 4 4 3-12 4 2 2 250-73 61 4 4 449-74