1646-933x 1646-933x S1646-933x2014000200053 10.1646‐933X-v7n2201407120005 Portugal 00 12 2014 00 12 2014 7 2 53 73

4 2 2 111-18 3 3 3 243-58 13 30 30 119-43 16 3 3 210-10 3 4 4 164-64 34 44 44 127-49 12 81-92 4 4 151-65 16 1 1 19-27 4 4 49-64