1981-0431 1981-0431 S1981-04312019000100600 10.26512/lc.v25.2019.23943 Portugal Portugal Portugal 00 01 2019 00 01 2019 25 2012 2017 51 2 2 5-27 2014 19 2 2 421-38 2002 2009 5th ed 2013 2015 15 3 3 715-40 1992